plucky (3) Mail::IMAPClient.3pm.gz

Provided by: libmail-imapclient-perl_3.43-1_all bug

NAME

       Mail::IMAPClient - An IMAP Client API

SYNOPSIS

         use Mail::IMAPClient;

         my $imap = Mail::IMAPClient->new(
           Server   => 'localhost',
           User     => 'username',
           Password => 'password',
           Ssl      => 1,
           Uid      => 1,
         );

         my $folders = $imap->folders
           or die "List folders error: ", $imap->LastError, "\n";
         print "Folders: @$folders\n";

         $imap->select( $Opt{folder} )
           or die "Select '$Opt{folder}' error: ", $imap->LastError, "\n";

         $imap->fetch_hash("FLAGS", "INTERNALDATE", "RFC822.SIZE")
           or die "Fetch hash '$Opt{folder}' error: ", $imap->LastError, "\n";

         $imap->logout
           or die "Logout error: ", $imap->LastError, "\n";

DESCRIPTION

       This module provides methods implementing the IMAP protocol to support interacting with IMAP message
       stores.

       The module is used by constructing or instantiating a new IMAPClient object via the "new" constructor
       method.  Once the object has been instantiated, the "connect" method is either implicitly or explicitly
       called.  At that point methods are available that implement the IMAP client commands as specified in
       RFC3501.  When processing is complete, the "logout" object method should be called.

       This documentation is not meant to be a replacement for RFC3501 nor any other IMAP related RFCs.

       Note that this documentation uses the term folder in place of RFC3501's use of mailbox.  This
       documentation reserves the use of the term mailbox to refer to the set of folders owned by a specific
       IMAP id.

   Connection State
       RFC3501 defines four possible states for an IMAP connection: not authenticated, authenticated, selected,
       and logged out.  These correspond to the IMAPClient constants "Connected", "Authenticated", "Selected",
       and "Unconnected", respectively.  These constants can be used in conjunction with the "Status" method to
       determine the status of an IMAPClient object and its underlying IMAP session.

       Note that an IMAPClient object can be in the "Unconnected" state both before a server connection is made
       and after it has ended.  This differs slightly from RFC3501, which does not define a pre-connection
       status.  For a discussion of the methods available for examining the IMAPClient object's status, see the
       section labeled "Status Methods", below.

   Advanced Authentication Mechanisms
       RFC3501 defines two commands for authenticating to an IMAP server:

       LOGIN
           LOGIN is for plain text authentication.

       AUTHENTICATE
           AUTHENTICATE for more advanced and/or secure authentication mechanisms.

       Mail::IMAPClient supports the following AUTHENTICATE mechanisms:

       DIGEST-MD5
           DIGEST-MD5 authentication requires the Authen::SASL and Digest::MD5 modules.  See also "Authuser".

       CRAM-MD5
           CRAM-MD5 requires the Digest::HMAC_MD5 module.

       PLAIN (SASL)
           PLAIN (SASL) authentication allows the optional use of the "Proxy" parameter.  RFC 4616 documents
           this syntax for SASL PLAIN:

             message = [authzid] UTF8NUL authcid UTF8NUL passwd

           When "Proxy" is defined, "User" is used as 'authzid' and "Proxy" is used as 'authcid'.  Otherwise,
           "User" is used as 'authcid'.

       NTLM
           NTLM authentication requires the Authen::NTLM module.  See also "Domain".

   Errors
       If you attempt an operation that results in an error, then you can retrieve the text of the error message
       by using the "LastError" method.  However, the "LastError" method is an object method (not a class
       method) and can only be used once an object is successfully created.  In cases where an object is not
       successfully created the $@ variable is set with an error message.

       Mail::IMAPClient resets $@ and "LastError" to undef before most IMAP requests, so the values only have a
       short lifespan.  "LastError" will always contain error info from the last error, until another error is
       encountered, another IMAP command is issued or it is explicitly cleared.

       Please note that the use of $@ is subject to change in the future release so it is best to use
       "LastError" for error checking once a Mail::IMAPClient object has been created.

       Errors in the "new" method can prevent your object from ever being created.  If the "Server", "User", and
       "Password" parameters are supplied to "new", it will attempt to call "connect" and "login".  Any of these
       methods could fail and cause the "new" method call to return "undef" and leaving the variable $@ is set
       to an error message.

       WARNING: (due to historical API behavior) on errors, many methods may return undef regardless of
       LIST/SCALAR context.  Therefore, it may be wise to use most methods in a scalar context.  Regardless,
       check "LastError" for details on errors.

   Transactions
       RFC3501 requires that each line in an IMAP conversation be prefixed with a tag.  A typical conversation
       consists of the client issuing a tag-prefixed command string, and the server replying with one of more
       lines of output.  Those lines of output will include a command completion status code prefixed by the
       same tag as the original command string.

       The IMAPClient module uses a simple counter to ensure that each client command is issued with a unique
       tag value.  This tag value is referred to by the IMAPClient module as the transaction number.  A history
       is maintained by the IMAPClient object documenting each transaction.  The "Transaction" method returns
       the number of the last transaction, and can be used to retrieve lines of text from the object's history.

       The "Clear" parameter is used to control the size of the session history so that long-running sessions do
       not eat up unreasonable amounts of memory.  See the discussion of "Clear" parameter for more information.

       The "Report" transaction returns the history of the entire IMAP session since the initial connection or
       for the last "Clear" transactions.  This provides a record of the entire conversation, including client
       command strings and server responses, and is a wonderful debugging tool as well as a useful source of raw
       data for custom parsing.

CLASS METHODS

       There are a couple of methods that can be invoked as class methods.  Generally they can be invoked as an
       object method as well.  Note that if the "new" method is called as an object method, the object returned
       is identical to what have would been returned if "new" had been called as a class method.  It doesn't
       give you a copy of the original object.

   new
       Example:

         my $imap = Mail::IMAPClient->new(%args)
           or die "new failed: $@\n";

       The "new" method creates a new instance of an IMAPClient object.

       If the "Server" parameter is passed as an argument to new, then new will implicitly call the "connect"
       method, placing the new object in the Connected state.  If "User" and "Password" values are also
       provided, then "connect" will in turn call "login", and the resulting object will be returned from new in
       the Authenticated state.

       If the "Server" parameter is not supplied then the IMAPClient object is created in the Unconnected state.

       If the new method is passed arguments then those arguments will be treated as a list of key=>value pairs.
       The key should be one of the parameters as documented under "Parameters" below.

       Here are some examples:

         use Mail::IMAPClient;

         # returns an unconnected Mail::IMAPClient object:
         my $imap = Mail::IMAPClient->new;
         # ...
         # intervening code using the 1st object, then:
         # (returns a new, authenticated Mail::IMAPClient object)
         $imap = Mail::IMAPClient->new(
             Server   => $host,
             User     => $id,
             Password => $pass,
             Clear    => 5,   # Unnecessary since '5' is the default
             # ...            # Other key=>value pairs go here
         ) or die "Cannot connect to $host as $id: $@";

       See also "Parameters", "connect" and "login" for more information on how to manually connect and login
       after new.

   Quote
       Example:

         $imap->search( HEADER => 'Message-id' => \$imap->Quote($msg_id) );

       The Quote method accepts a value as an argument and returns its argument as a correctly quoted string or
       a literal string.  Since version 3.17 Mail::IMAPClient automatically quotes search arguments we use a
       SCALARREF so search will not modify or re-quote the value returned by Quote.

       Note this method should not be used on folder names for Mail::IMAPClient methods, since methods that
       accept folder names as an argument will quote the folder name arguments automatically.

       If you are getting unexpected results when running methods with values that have (or might have) embedded
       spaces, double quotes, braces, or parentheses, then calling Quote may be necessary.  This method should
       not be used with arguments that are wrapped in quotes or parens if those quotes or parens are required by
       RFC3501.  For example, if the RFC requires an argument in this format:

         ( argument )

       and the argument is (or might be) "pennies (from heaven)", then one could use:

         $argument = "(" . $imap->Quote($argument) . ")"

       Of course, the fact that sometimes these characters are sometimes required delimiters is precisely the
       reason you must quote them when they are not delimiting.

       However, there are times when a method fails unexpectedly and may require the use of Quote to work.
       Should this happen, you can probably file a bug/enhancement request for Mail::IMAPClient to safeguard the
       particular call/case better.

       An example is RFC822 Message-id's, which usually don't contain quotes or parens.  When dealing with these
       it is usually best to take proactive, defensive measures from the very start and use Quote.

   Range
       Example:

         my $parsed = $imap->parse_headers(
             $imap->Range( $imap->messages ), "Date", "Subject"
         );

       The Range method will condense a list of message sequence numbers or message UID's into the most compact
       format supported by RFC3501.  It accepts one or more arguments, each of which can be:

       a) a message number,
       b) a comma-separated list of message numbers,
       c) a colon-separated range of message numbers (i.e. "$begin:$end")
       d) a combination of messages and message ranges, separated by commas (i.e. 1,3,5:8,10), or
       e) a reference to an array whose elements are like a) through d).

       The Range method returns a Mail::IMAPClient::MessageSet object.  The object uses overload and if treated
       as a string it will act like a string.  This means you can ignore its objectivity and just treat it like
       a string whose value is your message set expressed in compact format.

       This method provides an easy way to add or remove messages from a message set.

       For more information see Mail::IMAPClient::MessageSet.

   Rfc3501_date
       Example:

         $Rfc3501_date = $imap->Rfc3501_date($seconds);
         # or:
         $Rfc3501_date = Mail::IMAPClient->Rfc3501_date($seconds);

       The Rfc3501_date method accepts one input argument, a number of seconds since the epoch date.  It returns
       an RFC3501 compliant date string for that date (as required in date-related arguments to SEARCH, such as
       "since", "before", etc.).

   Rfc3501_datetime
       Example:

         $date = $imap->Rfc3501_datetime($seconds);
         # or:
         $date = Mail::IMAPClient->Rfc3501_datetime($seconds);

       The Rfc3501_datetime method accepts one or two arguments: a obligatory timestamp and an optional zone.
       The zone shall be formatted as "[+-]\d{4}", and defaults to +0000.  The timestamp follows the definition
       of the output of the platforms specific "time", usually in seconds since Jan 1st 1970.  However, you have
       to correct the number yourself for the zone.

   Rfc822_date
       Example:

         $Rfc822_date = $imap->Rfc822_date($seconds);
         # or:
         $Rfc822_date = Mail::IMAPClient->Rfc822_date($seconds);

       The Rfc822_date method accepts one input argument, a number of seconds since the epoch date.  It returns
       an RFC822 compliant date string for that date (without the 'Date:' prefix).  Useful for putting dates in
       message strings before calling "append", "search", etc.

   Strip_cr
       Examples:

         my $stripped = $imap->Strip_cr($string);
         # or:
         my @list = $imap->some_imap_method;
         @list = $imap->Strip_cr(@list);
         # or:
         my $list = [ $imap->some_imap_method ];   # returns an array ref
         $list = $imap->Strip_cr($list);

       The Strip_cr method strips carriage returns from input and returns the new string to the caller.  This
       method accepts one or more lines of text as arguments, and returns those lines with all <CR><LF>
       sequences changed to <LF>.  Any input argument with no carriage returns is returned unchanged.  If the
       first argument (not counting the class name or object reference) is an array reference, then members of
       that array are processed as above and subsequent arguments are ignored.  If the method is called in
       scalar context then an array reference is returned instead of an array of results.

       NOTE: Strip_cr does not remove new line characters.

OBJECT METHODS

       Object methods must be invoked against objects created via the "new" method and cannot be invoked as
       class methods.

       There object methods typically fall into one of two categories.  There are mailbox methods which
       participate in the IMAP session's conversation (i.e. they issue IMAP client commands) and object control
       methods which do not result in IMAP commands but which may affect later commands or provide details of
       previous ones.

       This object control methods can be further broken  down into two types, Parameter accessor methods, which
       affect the behavior of future mailbox methods, and "Status Methods", which report on the affects of
       previous mailbox methods.

       Methods that do not result in new IMAP client commands being issued (such as the "Transaction", "Status",
       and "History" methods) all begin with an uppercase letter, to distinguish them from methods that do
       correspond to IMAP client commands.  Class methods and eponymous parameter methods likewise begin with an
       uppercase letter because they also do not correspond to an IMAP client command.

       As a general rule, mailbox control methods return "undef" on failure and something besides "undef" when
       they succeed.  This rule is modified in the case of methods that return search results.  When called in a
       list context, searches that do not find matching results return an empty list.  When called in a scalar
       context, searches with no hits return 'undef' instead of an array reference.  If you want to know why you
       received no hits, you should check "LastError" or $@, which will be empty if the search was successful
       but had no matching results but populated with an error message if the search encountered a problem (such
       as invalid parameters).

       A number of IMAP commands do not have corresponding Mail::IMAPClient methods.  Patches are welcome.  In
       the pre-2.99 releases of this module, they were automatically created (AUTOLOAD), but that was very
       error-prone and stalled the progress of this module.

Mailbox Control Methods

   append
       Example:

         my $uid_or_true = $imap->append( $folder, $msgtext )
           or die "Could not append: ", $imap->LastError;

       WARNING: This method may be deprecated in the future, consider using "append_string" instead of this
       method.

       The append method adds a message to the specified folder.  See "append_string" for details as it is
       effectively an alias for that method.

       DEPRECATED BEHAVIOR: Additional arguments are added to the message text, separated with <CR><LF>.

   append_string
       Example:

          # brackets indicate optional arguments (not array refs):
          my $uidort = $imap->append_string( $folder, $msgtext [,$flags [,$date ] ] )
              or die "Could not append_string: ", $imap->LastError;

       Arguments:

       $folder
           the name of the folder to append the message to

       $msgtext
           the message text (including headers) of the message

       $flags
           An optional list of flags to set.  The list must be specified as a space-separated list of flags,
           including any backslashes that may be necessary and optionally enclosed by parenthesis.

       $date
           An optional RFC3501 date argument to set as the internal date.  It should be in the format described
           for date_time fields in RFC3501, i.e. "dd-Mon-yyyy hh:mm:ss +0000".

           If you want to specify a date/time but you don't want any flags then specify undef as the third
           ($flags) argument.

       Returns:

       error: undef
           On error, undef can be returned regardless of LIST/SCALAR context.  Check "LastError" for details.

       success: UID or $imap
           With UIDPLUS the UID of the new message is returned otherwise a true value (currently $self) is
           returned.

       To protect against "bare newlines", append will insert a carriage return before any newline that is
       "bare".

   append_file
       Example:

         my $new_msg_uid = $imap->append_file(
             $folder,
             $file,
             [ undef, $flags, $date ] # optional
         ) or die "Could not append_file: ", $imap->LastError;

       The append_file method adds a message to the specified folder.  Note: The brackets in the example
       indicate optional arguments; they do not mean that the argument should be an array reference.

       Arguments:

       $folder
           the name of the folder to append the message to

       $file
           a filename, filehandle or SCALAR reference which holds an RFC822-formatted message

       undef
           a deprecated argument used as a place holder for backwards compatibility

       $flags
           The optional argument is handled the same as append_string.

       $date
           The optional argument is handled the same as append_string (RFC3501 date), with the exception that if
           $date is "1" (one) then the modification time (mtime) of the file will be used.

       Returns:

       error: undef
           On error, undef can be returned regardless of LIST/SCALAR context.  Check "LastError" for details.

       success: UID or $imap
           With UIDPLUS the UID of the new message is returned otherwise a true value (currently $self) is
           returned.

       To protect against "bare newlines", append_file will insert a carriage return before any newline that is
       "bare".

       The append_file method provides a mechanism for allowing large messages to be appended without holding
       the whole file in memory.

       Version note: In 2.x an optional third argument to use for "input_record_separator" was allowed, however
       this argument is ignored/not supported as of 3.x.

   authenticate
       Example:

         $imap->authenticate( $authentication_mechanism, $coderef )
           or die "Could not authenticate: ", $imap->LastError;

       This method implements the AUTHENTICATE IMAP client command.  It can be called directly or may be called
       by "login" if the "Authmechanism" parameter is set to anything except 'LOGIN'.

       The authenticate method accepts two arguments, an authentication type to be used (ie CRAM-MD5) and a code
       or subroutine reference to execute to obtain a response.  The authenticate method assumes that the
       authentication type specified in the first argument follows a challenge-response flow.  The authenticate
       method issues the IMAP Client AUTHENTICATE command and receives a challenge from the server.  That
       challenge (minus any tag prefix or enclosing '+' characters but still in the original base64 encoding) is
       passed as the only argument to the code or subroutine referenced in the second argument.  The return
       value from the 2nd argument's code is written to the server as is, except that a <CR><LF> sequence is
       appended if necessary.

       If one or both of the arguments are not specified in the call to authenticate but their corresponding
       parameters have been set ("Authmechanism" and "Authcallback", respectively) then the parameter values are
       used. Arguments provided to the method call however will override parameter settings.

       If you do not specify a second argument and you have not set the "Authcallback" parameter, then the first
       argument must be one of the authentication mechanisms for which Mail::IMAPClient has built in support.

       See also the "login" method, which is the simplest form of authentication defined by RFC3501.

   before
       Example:

         my @msgs = $imap->before($Rfc3501_date)
           or warn "No messages found before $Rfc3501_date.\n";

       The before method works just like the "since" method, below, except it returns a list of messages whose
       internal system dates are before the date supplied as the argument to the before method.

   body_string
       Example:

         my $string = $imap->body_string($msgId)
           or die "body_string failed: ", $imap->LastError;

       The body_string method accepts a message sequence number (or a message UID, if the "Uid" parameter is set
       to true) as an argument and returns the message body as a string.  The returned value contains the entire
       message in one scalar variable, without the message headers.

   bodypart_string
       Example:

         my $string = $imap->bodypart_string(
             $msgid, $part_number, $length, $offset
         ) or die "Could not get bodypart string: ", $imap->LastError;

       The bodypart_string method accepts a message sequence number (or a message UID, if the "Uid" parameter is
       set to true) and a body part as arguments and returns the message part as a string.  The returned value
       contains the entire message part (or, optionally, a portion of the part) in one scalar variable.

       If an optional third argument is provided, that argument is the number of bytes to fetch.  (The default
       is the whole message part.)  If an optional fourth argument is provided then that fourth argument is the
       offset into the part at which the fetch should begin.  The default is offset zero, or the beginning of
       the message part.

       If you specify an offset without specifying a length then the offset will be ignored and the entire part
       will be returned.

       bodypart_string will return "undef" if it encounters an error.

   capability
       Example:

         my $features = $imap->capability
           or die "Could not determine capability: ", $imap->LastError;

       The capability method returns an array (or arrayref in scalar context) of capabilities as returned by the
       CAPABILITY IMAP client command.  If the CAPABILITY IMAP client command fails for any reason then the
       capability method will return "undef".  Supported capabilities are cached by the client, however, this
       cache is deleted after a connection is set to Authenticated and when "starttls" is called.

       See also "has_capability".

   close
       Example:

         $imap->close or die "Could not close: $@\n";

       The close method is used to close the currently selected folder via the CLOSE IMAP client command.
       According to RFC3501, the CLOSE command performs an implicit EXPUNGE, which means that any messages that
       are flagged as \Deleted (i.e. with the "delete_message" method) will now be deleted.  If you haven't
       deleted any messages then close can be thought of as an "unselect".

       Note: this closes the currently selected folder, not the IMAP session.

       See also "delete_message", "expunge", and RFC3501.

   compress
       Example:

         $imap->compress or die "Could not enable RFC4978 compression: $@\n";

       The compress method accepts no arguments.  This method is used to instruct the server to use the DEFLATE
       (RFC1951) compression extension.  See the "Compress" attribute for how to specify arguments for use
       during the initialization process.

       Version note: method added in Mail::IMAPClient 3.30

   connect
       Example:

         $imap->connect or die "Could not connect: $@\n";

       The connect method connects an imap object to the server.  It returns "undef" if it fails to connect for
       any reason.  If values are available for the "User" and "Password" parameters at the time that connect is
       invoked, then connect will call the "login" method after connecting and return the result of the "login"
       method to connect's caller.  If either or both of the "User" and "Password" parameters are unavailable
       but the connection to the server succeeds then connect returns a pointer to the IMAPClient object.

       The "Server" parameter must be set (either during "new" method invocation or via the "Server" object
       method) before invoking connect.  When the parameter is an absolute file path, an UNIX socket will get
       opened.  If the "Server" parameter is supplied to the "new" method then connect is implicitly called
       during object construction.

       The connect method sets the state of the object to "Connected" if it successfully connects to the server.
       It returns "undef" on failure.

   copy
       Example:

         # Here brackets indicate optional arguments:
         my $uidList = $imap->copy($folder, $msg_1 [ , ... , $msg_n ])
           or die "Could not copy: $@\n";

       Or:

         # Now brackets indicate an array ref!
         my $uidList = $imap->copy($folder, [ $msg_1, ... , $msg_n ])
           or die "Could not copy: $@\n";

       The copy method requires a folder name as the first argument, and a list of one or more messages sequence
       numbers (or messages UID's, if the UID parameter is set to a true value).  The message sequence numbers
       or UID's should refer to messages in the currently selected folder.  Those messages will be copied into
       the folder named in the first argument.

       The copy method returns "undef" on failure and a true value if successful.  If the server to which the
       current Mail::IMAPClient object is connected supports the UIDPLUS capability then the true value returned
       by copy will be a comma separated list of UID's, which are the UID's of the newly copied messages in the
       target folder.

   create
       Example:

         $imap->create($new_folder)
           or die "Could not create $new_folder: $@\n";

       The create method accepts one argument, the name of a folder (or what RFC3501 calls a "mailbox") to
       create.  If you specify additional arguments to the create method and your server allows additional
       arguments to the CREATE IMAP client command then the extra argument(s) will be passed to your server.

       If you specify additional arguments to the create method and your server does not allow additional
       arguments to the CREATE IMAP client command then the extra argument(s) will still be passed to your
       server and the create will fail.

       create returns a true value on success and "undef" on failure.

   date
       Example:

         my $date = $imap->date($msg);

       The date method accepts one argument, a message sequence number (or a message UID if the "Uid" parameter
       is set to a true value).  It returns the date of message as specified in the message's RFC822 "Date: "
       header, without the "Date: " prefix.

       The date method is a short-cut for:

         my $date = $imap->get_header($msg,"Date");

   delete
       Example:

         $imap->delete($folder) or die "Could not delete $folder: $@\n";

       The delete method accepts a single argument, the name of a folder to delete.  It returns a true value on
       success and "undef" on failure.

   deleteacl
       Example:

         $imap->deleteacl( $folder, $userid )
           or die "Could not delete acl: $@\n";

       The deleteacl method accepts two input arguments, a folder name, a user id (or authentication identifier,
       to use the terminology of RFC2086).  See RFC2086 for more information.  (This is somewhat experimental
       and its implementation may change.)

   delete_message
       Example:

         my @msgs = $imap->seen;
         scalar(@msgs) and $imap->delete_message(\@msgs)
           or die "Could not delete_message: $@\n";

       The above could also be rewritten like this:

         # scalar context returns array ref
         my $msgs = scalar($imap->seen);

         scalar(@$msgs) and $imap->delete_message($msgs)
           or die "Could not delete_message: $@\n";

       Or, as a one-liner:

         $imap->delete_message( scalar($imap->seen) )
           or warn "Could not delete_message: $@\n";
         # just give warning in case failure is
         # due to having no 'seen' msgs in the 1st place!

       The delete_message method accepts a list of arguments.  If the "Uid" parameter is not set to a true
       value, then each item in the list should be either:

       •   a message sequence number,

       •   a comma-separated list of message sequence numbers,

       •   a reference to an array of message sequence numbers, or

       If the "Uid" parameter is set to a true value, then each item in the list should be either:

       •   a message UID,

       •   a comma-separated list of UID's, or

       •   a reference to an array of message UID's.

       The messages identified by the sequence numbers or UID's will be deleted.  If successful, delete_message
       returns the number of messages it was told to delete.  However, since the delete is done by issuing the
       +FLAGS.SILENT option of the STORE IMAP client command, there is no guarantee that the delete was
       successful for every message.  In this manner the delete_message method sacrifices accuracy for speed.
       Generally, though, if a single message in a list of messages fails to be deleted it's because it was
       already deleted, which is what you wanted anyway so why worry about it? If there is a more severe error,
       i.e. the server replies "NO", "BAD", or, banish the thought, "BYE", then delete_message will return
       "undef".

       If you must have guaranteed results then use the IMAP STORE client command (via the default method) and
       use the +FLAGS (\Deleted) option, and then parse your results manually.

       Eg:

         $imap->store( $msg_id, '+FLAGS (\Deleted)' );
         my @results = $imap->History( $imap->Transaction );
           ...           # code to parse output goes here

       (Frankly I see no reason to bother with any of that; if a message doesn't get deleted it's almost always
       because it's already not there, which is what you want anyway.  But 'your mileage may vary' and all
       that.)

       The IMAPClient object must be in "Selected" status to use the delete_message method.

       NOTE: All the messages identified in the input argument(s) must be in the currently selected folder.
       Failure to comply with this requirement will almost certainly result in the wrong message(s) being
       deleted.

       ADDITIONAL NOTE: In the grand tradition of the IMAP protocol, deleting a message doesn't actually delete
       the message.  Really.  If you want to make sure the message has been deleted, you need to expunge the
       folder (via the "expunge" method, which is implemented via the default method).  Or at least "close" it.
       This is generally considered a feature, since after deleting a message, you can change your mind and
       undelete it at any time before your "expunge" or "close".

       See also: the "delete" method, to delete a folder, the "expunge" method, to expunge a folder, the
       "restore_message" method to undelete a message, and the "close" method (implemented here via the default
       method) to close a folder.  Oh, and don't forget about RFC3501.

   deny_seeing
       Example:

         # Reset all read msgs to unread
         # (produces error if there are no seen msgs):
         $imap->deny_seeing( scalar($imap->seen) )
           or die "Could not deny_seeing: $@\n";

       The deny_seeing method accepts a list of one or more message sequence numbers, or a single reference to
       an array of one or more message sequence numbers, as its argument(s).  It then unsets the "\Seen" flag
       for those messages (so that you can "deny" that you ever saw them).  Of course, if the "Uid" parameter is
       set to a true value then those message sequence numbers should be unique message id's.

       Note that specifying "$imap->deny_seeing(@msgs)" is just a shortcut for specifying
       "$imap->unset_flag("Seen",@msgs)".

   disconnect
       Example:

         $imap->disconnect or warn "Could not logout: $@\n";

       This method calls "logout", see "logout" for details.

   done
       Example:

         my $tag = $imap->idle or warn "idle failed: $@\n";
         doSomethingA();
         my $idlemsgs = $imap->idle_data() or warn "idle_data error: $@\n";
         doSomethingB();
         my $results = $imap->done($tag) or warn "Error from done: $@\n";

       The done method tells the IMAP server to terminate the IDLE command.  The only argument is the tag
       (identifier) received from the previous call to "idle".  If tag is not specified a default tag based on
       the Count attribute is assumed to be the tag to look for in the response from the server.

       If an invalid tag is specified, or the default tag is wrong, then done will hang indefinitely or until a
       timeout occurs.

       If done is called when an "idle" command is not active then the server will likely respond with an error
       like * BAD Invalid tag.

       On failure <undef> is returned and "LastError" is set.

       See also "idle", "idle_data" and "Results".

   examine
       Example:

         $imap->examine($folder) or die "Could not examine: $@\n";

       The examine method selects a folder in read-only mode and changes the object's state to "Selected".  The
       folder selected via the examine method can be examined but no changes can be made unless it is first
       selected via the "select" method.

       The examine method accepts one argument, which is the name of the folder to select.

   exists
       Example:

         $imap->exists($folder) or warn "$folder not found: $@\n";

       Accepts one argument, a folder name.  Returns true if the folder exists or false if it does not exist.

   expunge
       Example:

         $imap->expunge($folder) or die "Could not expunge: $@\n";

       The expunge method accepts one optional argument, a folder name.  It expunges the folder specified as the
       argument, or the currently selected folder (if any) when no argument is supplied.

       Although RFC3501 does not permit optional arguments (like a folder name) to the EXPUNGE client command,
       the "expunge" method does.  Note: expunging a folder deletes the messages that have the \Deleted flag set
       (i.e. messages flagged via "delete_message").

       See also the "close" method, which "deselects" as well as expunges.

   fetch
       Usage:

         $imap->fetch( [$seq_set|ALL], @msg_data_items )

       Example:

         my $output = $imap->fetch(@args) or die "Could not fetch: $@\n";

       The fetch method implements the FETCH IMAP client command.  It accepts a list of arguments, which will be
       converted into a space-delimited list of arguments to the FETCH IMAP client command.  If no arguments are
       supplied then fetch does a FETCH ALL.  If the "Uid" parameter is set to a true value then the first
       argument will be treated as a UID or list of UID's, which means that the UID FETCH IMAP client command
       will be run instead of FETCH.  (It would really be a good idea at this point to review RFC3501.)

       If called in array context, fetch will return an array of output lines.  The output lines will be
       returned just as they were received from the server, so your script will have to be prepared to parse out
       the bits you want.  The only exception to this is literal strings, which will be inserted into the output
       line at the point at which they were encountered (without the {nnn} literal field indicator).  See
       RFC3501 for a description of literal fields.

       If fetch is called in a scalar context, then a reference to an array (as described above) is returned
       instead of the entire array.

       fetch returns "undef" on failure.  Inspect "LastError" or $@ for an explanation of your error.

   fetch_hash
       Usage:

         $imap->fetch_hash( [$seq_set|ALL], @msg_data_items, [\%msg_by_ids] )

       Examples:

         my $hashref = $imap->fetch_hash("RFC822.SIZE");

        OR

         my $hashref = {};
         $imap->fetch_hash( "RFC822.SIZE", $hashref );
         print "Msg #$_ is $hashref->{$_}->{'RFC822.SIZE'} bytes\n" for (keys %$hashref);

       The fetch_hash method accepts a list of message attributes to be fetched (as described in RFC3501).  It
       returns a hash whose keys are all the messages in the currently selected folder and whose values are key-
       value pairs of fetch keywords and the message's value for that keyword (see sample output below).

       If fetch_hash is called in scalar context, it returns a reference to the hash instead of the hash itself.
       If the last argument is a hash reference, then that hash reference will be used as the place where
       results are stored (and that reference will be returned upon successful completion).  If the last
       argument is not a reference then it will be treated as one of the FETCH attributes and a new hash will be
       created and returned (either by value or by reference, depending on the context in which fetch_hash was
       called).

       For example, if you have a folder with 3 messages and want the size and internal date for each of them,
       you could do the following:

         use Mail::IMAPClient;
         use Data::Dumper;
         # ... other code goes here
         $imap->select($folder);
         my $hash = $imap->fetch_hash( "RFC822.SIZE", "INTERNALDATE" );
         # (Same as:
         #  my $hash = $imap->fetch_hash("RFC822.SIZE");
         #  $imap->fetch_hash( "INTERNALDATE", $hash );
         # ).
         print Data::Dumper->Dumpxs( [$hash], ['$hash'] );

       This would result in Data::Dumper output similar to the following:

          $hash = {
              '1' => {
                         'INTERNALDATE' => '21-Sep-2002 18:21:56 +0000',
                         'RFC822.SIZE' => '1586',
                     },
              '2' => {
                         'INTERNALDATE' => '22-Sep-2002 11:29:42 +0000',
                         'RFC822.SIZE' => '1945',
                     },
              '3' => {
                         'INTERNALDATE' => '23-Sep-2002 09:16:51 +0000',
                         'RFC822.SIZE' => '134314',
                     }
            };

       By itself this method may be useful for tasks like obtaining the size of every message in a folder.  It
       issues one command and receives one (possibly long!) response from the server.

       If the fetch request causes the server to return data in a parenthesized list, the data within the
       parenthesized list may be escaped via the Escape() method. Use the Unescape() method to get the raw
       values back in this case.

   flags
       Example:

         my $flags = $imap->flags($msgid)
           or die "flags failed: $@\n";

       The flags method implements the FETCH IMAP client command to list a single message's flags.  It accepts
       one argument, a message sequence number (or a message UID, if the "Uid" parameter is true), and returns
       an array (or a reference to an array, if called in scalar context) listing the flags that have been set.
       Flag names are provided with leading backslashes.

       As of version 1.11, you can supply either a list of message id's or a reference to an array of message
       id's (which means either sequence number, if the Uid parameter is false, or message UID's, if the Uid
       parameter is true) instead of supplying a single message sequence number or UID.  If you do, then the
       return value will not be an array or array reference; instead, it will be a hash reference, with each key
       being a message sequence number (or UID) and each value being a reference to an array of flags set for
       that message.

       For example, if you want to display the flags for every message in the folder where you store e-mail
       related to your plans for world domination, you could do something like this:

         use Mail::IMAPClient;
         my $imap = Mail::IMAPClient->new(
             Server   => $imaphost,
             User     => $login,
             Password => $pass,
             Uid      => 1,        # optional
         );

         $imap->select("World Domination");
         # get the flags for every message in my 'World Domination' folder
         $flaghash = $imap->flags( scalar( $imap->search("ALL") ) );

         # pump through sorted hash keys to print results:
         for my $k ( sort { $flaghash->{$a} <=> $flaghash->{$b} } keys %$flaghash ) {
             # print: Message 1: \Flag1, \Flag2, \Flag3
             print "Message $k:\t", join( ", ", @{$flaghash->{$k}} ), "\n";
         }

   folders
       Example:

         $imap->folders or die "Could not list folders: $@\n";

       The folders method returns an array listing the available folders.  It will only be successful if the
       object is in the Authenticated or Selected states.

       The folders method accepts one optional argument, which is a prefix.  If a prefix is supplied to the
       folders method, then only folders beginning with the prefix will be returned.

       For example:

         print join( ", ", $imap->folders ), ".\n";
         # Prints:
         # INBOX, Sent, Projects, Projects/Completed, Projects/Ongoing, Projects Software.
         print join( ", ", $imap->folders("Projects") ), ".\n";
         # Prints:
         # Projects, Projects/Completed, Projects/Ongoing, Projects Software.
         print join( ", ", $imap->folders("Projects" . $imap->separator) ), ".\n";
         # Prints:
         # Projects/Completed, Projects/Ongoing

       Please note that documentation previously suggested that if you just want to list a folder's subfolders
       (and not the folder itself), then you need to include the hierarchy separator character (as returned by
       the "separator" method). However, this does not match the behavior of the existing implementation, so you
       will need to manually exclude the parent folder from the results.

   folders_hash
         my @fhashes = $imap->folders_hash
           or die "Could not get list of folder hashes.\n";

       The folders_hash method accepts one optional argument, which is a prefix.  If a prefix is supplied to the
       folders_hash method, then only folders beginning with the prefix will be returned.

       An array(ref) of hashes is returned that contain information about the requested folders.  Each hash
       contains three keys (name, attrs, delim) and looks like the following:

         {
           name  => 'Mail/Box/Name',
           attrs => [ '\Marked', '\HasNoChildren' ],
           delim => '/',
         }

       IMAP servers implementing RFC6154 return attributes to be used to identify special-use mailboxes
       (folders).

         my $sattr_re = /\A\\(?:All|Archive|Drafts|Flagged|Junk|Sent|Trash)\Z/;
         foreach my $fhash (@fhashes) {
             next unless defined $fhash->{name};
             my @special = grep { $sattr_re } @{ $fhash->{attrs} };
             print("special: $fhash->{name} : @special\n") if (@special);
         }

       Version note: method added in Mail::IMAPClient 3.34

   xlist_folders (DEPRECATED)
       This method is deprecated as of version 3.34.  Please use folders_hash instead.  See RFC6154 for
       attributes to be used to identify special-use mailboxes (folders).

       Example:

         my $xlist = $imap->xlist_folders
           or die "Could not get xlist folders.\n";

       IMAP servers implementing the XLIST extension (such as Gmail) designate particular folders to be used for
       particular functions.  This is useful in the case where you want to know which folder should be used for
       Trash when the actual folder name can't be predicted (e.g. in the case of Gmail, the folder names change
       depending on the user's locale settings).

       The xlist_folders method returns a hash listing any "xlist" folder names, with the values listing the
       actual folders that should be used for those names.  For example, using this method with a Gmail user
       using the English (US) locale might give this output from Data::Dumper:

         $VAR1 = {
             'Inbox'   => 'Inbox',
             'AllMail' => '[Gmail]/All Mail',
             'Trash'   => '[Gmail]/Trash',
             'Drafts'  => '[Gmail]/Drafts',
             'Sent'    => '[Gmail]/Sent Mail',
             'Spam'    => '[Gmail]/Spam',
             'Starred' => '[Gmail]/Starred'
         };

       The same list for a user using the French locale might look like this:

         $VAR1 = {
             'Inbox'   => 'Bo&AO4-te de r&AOk-ception',
             'AllMail' => '[Gmail]/Tous les messages',
             'Trash'   => '[Gmail]/Corbeille',
             'Drafts'  => '[Gmail]/Brouillons',
             'Sent'    => '[Gmail]/Messages envoy&AOk-s',
             'Spam'    => '[Gmail]/Spam',
             'Starred' => '[Gmail]/Suivis'
         };

       Mail::IMAPClient recognizes the following "xlist" folder names:

       Inbox
       AllMail
       Trash
       Drafts
       Sent
       Spam
       Starred

       These are currently the only ones supported by Gmail.  The XLIST extension is not documented, and there
       are no other known implementations other than Gmail, so this list is based on what Gmail provides.

       If the server does not support the XLIST extension, this method returns undef.

       Version note: method added in Mail::IMAPClient 3.21

   has_capability
       Example:

         my $has_feature = $imap->has_capability($feature)
           or die "Could not do has_capability($feature): $@\n";

       Returns:

       "undef"
           If the underlying "capability" calls fails then "undef" is returned.

       "" or "()"
           If the server does not have the requested capability, then either an empty string ("" in scalar
           context) or an empty list ("()" in list context) is returned.

       a true value
           If the server has the requested capability, then a true value is returned.  The true value depends
           upon the server response for the capability requested.  The value will be an array reference in
           scalar context or an array in list context. The returned data is useful for understanding more about
           specific capabilities.  For example, consider the following server CAPABILITY response:

             * CAPABILITY IMAP4rev1 SORT SORT=DISPLAY I18NLEVEL=1 AUTH=PLAIN AUTH=XTEST

           Results are returned as shown by the trailing comments:

             $c = $imap->has_capability("IMAP4rev1");    # [ "IMAP4rev1" ]
             @c = $imap->has_capability("IMAP4rev1");    # ( "IMAP4rev1" )
             $c = $imap->has_capability("SORT");         # [ "DISPLAY" ]
             @c = $imap->has_capability("SORT=DISPLAY"); # ( "SORT=DISPLAY" )
             $c = $imap->has_capability("AUTH");         # [ "PLAIN", "XTEST" ]
             @c = $imap->has_capability("AUTH");         # ( "PLAIN", "XTEST" )
             $c = $imap->has_capability("AUTH=XTEST");   # [ "AUTH=XTEST" ]
             @c = $imap->has_capability("AUTH=XTEST");   # ( "AUTH=XTEST" )
             $c = $imap->has_capability("AUTH=NADA");    # ''
             @c = $imap->has_capability("AUTH=NADA");    # ()
             $c = $imap->has_capability("NADA");         # ''
             @c = $imap->has_capability("NADA");         # ()

   idle
       Example:

         my $tag = $imap->idle or warn "idle failed: $@\n";
         doSomethingA();
         my $idlemsgs = $imap->idle_data() or warn "idle_data error: $@\n";
         doSomethingB();
         my $results = $imap->done($tag) or warn "Error from done: $@\n";

       The idle method tells the IMAP server the client is ready to accept unsolicited mailbox update messages
       (on the selected folder/mailbox).  This method is only valid on servers that support the IMAP IDLE
       extension, see RFC2177 for details.

       The idle method accepts no arguments and returns the tag (identifier) that was sent by the client for
       this command.  This tag should be supplied as the argument to "done" when ending the IDLE command.

       On failure <undef> is returned and "LastError" is set.

       The method "idle_data" may be used once idle has been successful.  However, no mailbox operations may be
       called until the idle command has been terminated by calling "done".  Failure to do so will result in an
       error and the idle command will typically be terminated by the server.

       See also "idle_data" and "done".

   idle_data
       Usage:

         # an optional timeout in seconds may be specified
         $imap->idle_data( [$timeout] )

       Example:

         my $tag = $imap->idle or warn "idle failed: $@\n";
         doSomethingA();
         my $idlemsgs = $imap->idle_data() or warn "idle_data error: $@\n";
         doSomethingB();
         my $results = $imap->done($tag) or warn "Error from done: $@\n";

       The idle_data method can be used to accept any unsolicited mailbox update messages that have been sent by
       the server during an "idle" command.  This method does not send any commands to the server, it simply
       looks for and optionally waits for data from the server and returns that data to the caller.

       The idle_data method accepts an optional $timeout argument and returns an array (or an array reference if
       called in scalar context) with the messages from the server.

       By default a timeout of 0 seconds is used (do not block).  Internally the timeout is passed to "select"
       in perlfunc.  The timeout controls how long the select call blocks if there are no messages waiting to be
       read from the server.

       On failure <undef> is returned and "LastError" is set.

       See also "imap" and "done".

       Version note: method added in Mail::IMAPClient 3.23 Warning: this method is considered experimental and
       the interface/output may change in a future version.

   imap4rev1
       Example:

         $imap->imap4rev1 or die "Could not imap4rev1: $@\n";

       Returns true if the IMAP server to which the IMAPClient object is connected has the IMAP4REV1 capability.
       If the server does not have the capability then the empty string "" is returned, if the underlying
       "capability" calls fails then undef is returned.

   internaldate
       Example:

         my $msg_internal_date = $imap->internaldate($msgid)
           or die "internaldate failed: $@\n";

       internaldate accepts one argument, a message id (or UID if the "Uid" parameter is true), and returns that
       message's internal date or undef if the call fails or internal date is not returned.

   get_bodystructure
       Example:

         my $bodyStructObject = $imap->get_bodystructure($msgid)
           or die "Could not get_bodystructure: $@\n";

       The get_bodystructure method accepts one argument, a message sequence number or, if "Uid" is true, a
       message UID.  It obtains the message's body structure and returns a parsed
       Mail::IMAPClient::BodyStructure object for the message.

   get_envelope
       Example:

         my $envObject = $imap->get_envelope(@args)
           or die "Could not get_envelope: $@\n";

       The get_envelope method accepts one argument, a message sequence number or, if "Uid" is true, a message
       UID.  It obtains the message's envelope and returns a Mail::IMAPClient::BodyStructure::Envelope object
       for the envelope, which is just a version of the envelope that's been parsed into a Perl object.

       For more information on how to use this object once you've gotten it, see the
       Mail::IMAPClient::BodyStructure documentation.  (As of this writing there is no separate pod document for
       Mail::IMAPClient::BodyStructure::Envelope.)

   getacl
       Example:

         my $hash = $imap->getacl($folder)
           or die "Could not getacl for $folder: $@\n";

       getacl accepts one argument, the name of a folder.  If no argument is provided then the currently
       selected folder is used as the default.  It returns a reference to a hash.  The keys of the hash are
       userids that have access to the folder, and the value of each element are the permissions for that user.
       The permissions are listed in a string in the order returned from the server with no white space or
       punctuation between them.

   get_header
       Example:

         my $messageId = $imap->get_header( $msg, "Message-Id" );

       The get_header method accepts two arguments, a message sequence number or UID and the name of an RFC822
       header (without the trailing colon).  It returns the value for that header in the message whose sequence
       number or UID was passed as the first argument.  If no value can be found it returns "undef"; if multiple
       values are found it returns the first one.  Its return value is always a scalar.  get_header uses case
       insensitive matching to get the value, so you do not have to worry about the case of your second
       argument.

       The get_header method is a short-cut for:

         my $messageId = $imap->parse_headers($msg,"Subject")->{"Subject"}[0];

   getquotaroot
       Example:

         my $results = $imap->getquotaroot($mailboxname)
           or die "Could not getquotaroot for $mailboxname: $@\n";

       The getquotaroot method implements the RFC2087 GETQUOTAROOT command.  The "$mailboxname" defaults to
       "INBOX" if no argument is provided.

       On error "undef" is returned, otherwise "Results" are returned.  The results should have the untagged
       QUOTAROOT response from the server along with the QUOTAROOT's resource usage and limits in an untagged
       QUOTA response.

       See also RFC2087, "getquota", "setquota", "quota" and "quota_usage".

   getquota
       Example:

         my $results = $imap->getquota($quotaroot)
           or die "Could not getquota for $quotaroot: $@\n";

       The getquota method implements the RFC2087 GETQUOTA command.  The "$quotaroot" defaults to "user/User" if
       no argument is provided.

       On error "undef" is returned, otherwise "Results" are returned.  The results from the server should have
       the untagged QUOTA response from the server.

       See also RFC2087, "getquotaroot", "quota" and "quota_usage".

   quota
       Example:

         my $limit = $imap->quota($quotaroot)
           or die "Could not get quota limit for $quotaroot: $@\n";

       The quota method takes the "Results" from getquota and parses out the "STORAGE" limit returned by the
       server.  The "$quotaroot" defaults to "INBOX" if no argument is provided.

       On error "undef" is returned, otherwise the integer "STORAGE" limit provided by the server is returned.

       See also RFC2087, "getquotaroot", "getquota" and "quota_usage".

   quota_usage
       Example:

         my $usage = $imap->quota_usage($quotaroot)
           or die "Could not get quota usage for $quotaroot: $@\n";

       The quota_usage method takes the "Results" from getquota and parses out the "STORAGE" usage returned by
       the server.  The "$quotaroot" defaults to "INBOX" if no argument is provided.

       On error "undef" is returned, otherwise the integer "STORAGE" usage provided by the server is returned.

       See also RFC2087, "getquotaroot", "getquota" and "quota".

   setquota
       Example:

         my $results = $imap->setquota( $quotaroot, $resource, $limit )
           or die "Could not setquota for $quotaroot: $@\n";

       The setquota method implements the RFC2087 SETQUOTA command.  It accepts multiple pairs of $resource and
       $limit arguments.  The "$quotaroot" defaults to "user/User" if not defined.

       On error "undef" is returned, otherwise "Results" are returned.

       See also RFC2087, "getquotaroot" and "getquota".

   is_parent
       Example:

         my $hasKids = $imap->is_parent($folder);

       The is_parent method accepts one argument, the name of a folder. It returns a value that indicates
       whether or not the folder has children.  The value it returns is either:

       1 (or a positive integer)
           The "\HasChildren" attribute is set, indicating that the folder has children.

       0 (zero)
           The "\HasNoChildren" attribute is set, indicating that the folder has no children at this time.

       "undef"
           The "\NoInferiors" attribute is set, indicating the folder is not permitted to have children.

       Eg:

         my $parenthood = $imap->is_parent($folder);
         if ( defined($parenthood) ) {
             if ($parenthood) {
                 print "$folder has children.\n";
             }
             else {
                 print "$folder is permitted children, but has none.\n";
             }
         }
         else {
             print "$folder is not permitted to have children.\n";
         }

   list
       Example:

         my @raw_output = $imap->list(@args)
           or die "Could not list: $@\n";

       The list method implements the IMAP LIST client command.  Arguments are passed to the IMAP server as
       received, separated from each other by spaces.  If no arguments are supplied then the default list
       command "tag LIST "" '*'" is issued.

       The list method returns an array (or an array reference, if called in a scalar context).  The array is
       the unadulterated output of the LIST command.  (If you want your output adulterated then see the
       "folders" method, above.)

       An "undef" value is returned in case of errors.  Be sure to check for it.

   listrights
       Example:

         $imap->listrights( $folder, $user )
           or die "Could not listrights: $@\n";

       The listrights method implements the IMAP LISTRIGHTS client command (RFC2086).  It accepts two arguments,
       the foldername and a user id.  It returns the rights the specified user has for the specified folder.  If
       called in a scalar context then the rights are returned a strings, with no punctuation or white space or
       any nonsense like that.  If called in array context then listrights returns an array in which each
       element is one right.

   login
       Example:

         $imap->login or die "Could not login: $@\n";

       The login method implements the IMAP LOGIN client command to log into the server.  It automatically calls
       "authenticate" if the Authmechanism parameter is set to anything except 'LOGIN' otherwise a clear text
       LOGIN is attempted.

       The User and Password parameters must be set before the login method can be invoked.  On success, a
       Mail::IMAPClient object with the Status of Authenticated is returned.  On failure, undef is returned and
       $@ is set.  The methods "new", "connect", and "Socket" may automatically invoke login see the
       documentation of each method for details.

       If the "Compress" parameter is set, the "compress" method will automatically be called after successful
       authentication.

       See also "proxyauth" and "Proxy" for additional information regarding ways of authenticating with a
       server via SASL and/or PROXYAUTH.

   proxyauth
       Example:

         $imap->login( "admin", "password" );
         $imap->proxyauth("someuser");

       The proxyauth method implements the IMAP PROXYAUTH client command.  The command is used by
       Sun/iPlanet/Netscape IMAP servers to allow an administrative user to masquerade as another user.

   logout
       Example:

         $imap->logout or die "Could not logout: $@\n";

       The logout method implements the LOGOUT IMAP client command.  This method causes the server to end the
       connection and the IMAPClient client enters the Unconnected state.  This method does not, destroy the
       IMAPClient object, thus the "connect" and "login" methods can be used to establish a new IMAP session.

       Note that RFC2683 section 3.1.2 (Severed connections) makes some recommendations on how IMAP clients
       should behave.  It is up to the user of this module to decide on the preferred behavior and code
       accordingly.

       Version note: documentation (from 2.x through 3.23) claimed that Mail::IMAPClient would attempt to log
       out of the server during DESTROY if the object is in the "Connected" state.  This documentation was
       apparently incorrect from at least 2.2.2 and possibly earlier versions on up.

   lsub
       Example:

         $imap->lsub(@args) or die "Could not lsub: $@\n";

       The lsub method implements the IMAP LSUB client command.  Arguments are passed to the IMAP server as
       received, separated from each other by spaces.  If no arguments are supplied then the default lsub
       command "tag LSUB "" '*'" is issued.

       The lsub method returns an array (or an array reference, if called in a scalar context).  The array is
       the unaltered output of the LSUB command.  If you want an array of subscribed folders then see the
       "subscribed" method, below.

   mark
       Example:

         $imap->mark(@msgs) or die "Could not mark: $@\n";

       The mark method accepts a list of one or more messages sequence numbers, or a single reference to an
       array of one or more message sequence numbers, as its argument(s).  It then sets the "\Flagged" flag for
       those message(s).  Of course, if the "Uid" parameter is set to a true value then those message sequence
       numbers had better be unique message id's.

       Note that specifying "$imap->see(@msgs)" is just a shortcut for specifying
       "$imap->set_flag("Flagged",@msgs)".

   Massage
       Example:

         $imap->search(HEADER => 'Message-id' => $imap->Massage($msg_id,1));

       WARNING: This method may be deprecated in the future, consider using "Quote" instead of this method.

       The Massage method accepts a value as an argument and, optionally, a second value that, when true,
       indicates that the first argument is not the name of an existing folder.

       WARNING: If the first argument has double quotes at the beginning and end of its value, those double
       quote will be stripped unless the second argument does not evaluate to true.

       It returns its argument as a correctly quoted string or a literal string.

       Note that you should rarely use this on folder names, since methods that accept folder names as an
       argument will call Quote for you.

   message_count
       Example:

         my $msgcount = $imap->message_count($folder);
         defined($msgcount) or die "message_count failed: $@\n";

       The message_count method accepts the name of a folder as an argument and returns the number of messages
       in that folder.  Internally, it invokes the "status" method (see above) and parses out the results to
       obtain the number of messages.  If you don't supply an argument to message_count then it will return the
       number of messages in the currently selected folder (assuming of course that you've used the "select" or
       "examine" method to select it instead of trying something funky).  Note that RFC2683 contains warnings
       about the use of the IMAP STATUS command (and thus the "status" method and therefore the message_count
       method) against the currently selected folder.  You should carefully consider this before using
       message_count on the currently selected folder.  You may be better off using "search" or one of its
       variants (especially "messages"), and then counting the results.  On the other hand, I regularly violate
       this rule on my server without suffering any dire consequences.  Your mileage may vary.

   message_string
       Example:

         my $string = $imap->message_string($msgid)
           or die "message_string failed: $@\n";

       The message_string method accepts a message sequence number (or message UID if "Uid" is true) as an
       argument and returns the message as a string.  The returned value contains the entire message in one
       scalar variable, including the message headers.  Note that using this method will set the message's
       "\Seen" flag as a side effect, unless Peek is set to a true value.

   message_to_file
       Example:

         $imap->message_to_file( $file, @msgs )
           or die "message_to_file failed: $@\n";

       The message_to_file method accepts a filename or file handle and one or more message sequence numbers (or
       message UIDs if "Uid" is true) as arguments and places the message string(s) (including RFC822 headers)
       into the file named in the first argument (or prints them to the file handle, if a file handle is
       passed).  The returned value is true on success and "undef" on failure.

       If the first argument is a reference, it is assumed to be an open file handle and will not be closed when
       the method completes, If it is a file, it is opened in append mode, written to, then closed.

       Note that using this method will set the message's "\Seen" flag as a side effect.  But you can use the
       "deny_seeing" method to set it back, or set the "Peek" parameter to a true value to prevent setting the
       "\Seen" flag at all.

       This method currently works by making some basic assumptions about the server's behavior, notably that
       the message text will be returned as a literal string but that nothing else will be.  If you have a
       better idea then I'd like to hear it.

   message_uid
       Example:

         my $msg_uid = $imap->message_uid($msg_seq_no)
           or die "Could not get uid for $msg_seq_no: $@\n";

       The message_uid method accepts a message sequence number (or message UID if "Uid" is true) as an argument
       and returns the message's UID.  Yes, if "Uid" is true then it will use the IMAP UID FETCH UID client
       command to obtain and return the very same argument you supplied.  This is an IMAP feature so don't
       complain to me about it.

   messages
       Example:

         # Get a list of messages in the current folder:
         my @msgs = $imap->messages or warn "Could not list messages\n";
         # Get a reference to an array of messages in the current folder:
         my $msgs = $imap->messages or die "Get messages failed: $@\n";

       If called in list context, the messages method returns a list of all the messages in the currently
       selected folder.  If called in scalar context, it returns a reference to an array containing all the
       messages in the folder.  This is the same as specifying "$imap->"search"("ALL")".

       An empty list is returned when no messages are found.  On failure <undef> is returned and "LastError" is
       set.

   migrate
       Example:

         $imap_src->migrate( $imap_dest, "ALL", $targetFolder )
           or die "Could not migrate: ", $imap_src->LastError;

       The migrate method copies the indicated message(s) from the currently selected folder to another
       Mail::IMAPClient object's session.  It requires these arguments:

       1.  a reference to the target Mail::IMAPClient object (not the calling object, which is connected to the
           source account);

       2.  the message(s) to be copied, specified as either a) the message sequence number (or message UID if
           the UID parameter is true) of a single message, b) a reference to an array of message sequence
           numbers (or message UID's if the UID parameter is true) or c) the special string "ALL", which is a
           shortcut for the results of ""search"("ALL")".

       3.  the name of the destination folder on the target mailbox to receive the message(s).  If this argument
           is not supplied or is undef then the currently selected folder on the calling object will be used.
           The destination folder will be automatically created if necessary.

       The target ($imap_dest) Mail::IMAPClient object must not be the same object as the source ($imap_src).

       This method does not attempt to minimize memory usage.  In the future it could be enhanced to
       (optionally) write message data to a temporary file to avoid storing the entire message in memory.

       To work around potential network timeouts on large messages, consider setting "Reconnectretry" to 1 on
       both $imap_src and $imap_dest.

       See also "Supportedflags".

   move
       Example:

         my $newUid = $imap->move( $newFolder, $oldUid )
           or die "Could not move: $@\n";
         $imap->expunge;

       The move method moves messages from the currently selected folder to the folder specified in the first
       argument to move.  If the "Uid" parameter is not true, then the rest of the arguments should be either:

       a)  a message sequence number,

       b)  a comma-separated list of message sequence numbers, or

       c)  a reference to an array of message sequence numbers.

       If the "Uid" parameter is true, then the arguments should be:

       a)  a message UID,

       b)  a comma-separated list of message UID's, or

       c)  a reference to an array of message UID's.

       If the target folder does not exist then it will be created.

       If move is successful, then it returns a true value.  Furthermore, if the Mail::IMAPClient object is
       connected to a server that has the UIDPLUS capability, then the true value will be the comma-separated
       list of UID's for the newly copied messages.  The list will be in the order in which the messages were
       moved which should correspond to the order of the message UID provided by the caller.

       If the move is not successful then move returns "undef".

       Note that a move really just involves copying the message to the new folder and then setting the \Deleted
       flag.  To actually delete the original message you will need to run "expunge" (or "close").

   namespace
       Example:

         my $refs = $imap->namespace
           or die "namespace failed: $@\n";

       The namespace method runs the NAMESPACE IMAP command (as defined in RFC 2342).  When called in a list
       context, it returns a list of three references.  Each reference looks like this:

         [
           [ $prefix_1, $separator_1 ],
           [ $prefix_2, $separator_2 ],
           [ $prefix_n, $separator_n ],
         ]

       The first reference provides a list of prefixes and separator characters for the available personal
       namespaces.  The second reference provides a list of prefixes and separator characters for the available
       shared namespaces.  The third reference provides a list of prefixes and separator characters for the
       available public namespaces.

       If any of the three namespaces are unavailable on the current server then an 'undef' is returned instead
       of a reference.  So for example if shared folders were not supported on the server but personal and
       public namespaces were both available (with one namespace each), the returned value might resemble this:

         [ [ "", "/" ] , undef, [ "#news", "." ] ];

       If the namespace method is called in scalar context, it returns a reference to the above-mentioned list
       of three references, thus creating a single structure that would pretty-print something like this:

         $VAR1 = [
             [
                 [ $user_prefix_1, $user_separator_1 ],
                 [ $user_prefix_2, $user_separator_2 ],
                 [ $user_prefix_n, $user_separator_n ],
             ],                    # or undef
             [
                 [ $shared_prefix_1, $shared_separator_1 ],
                 [ $shared_prefix_2, $shared_separator_2 ],
                 [ $shared_prefix_n, $shared_separator_n ],
             ],                    # or undef
             [
                 [ $public_prefix_1, $public_separator_1 ],
                 [ $public_prefix_2, $public_separator_2 ],
                 [ $public_prefix_n, $public_separator_n ],
             ],                    # or undef
         ];

   on
       Example:

         my @msgs = $imap->on($Rfc3501_date)
           or warn "Could not find messages sent on $Rfc3501_date: $@\n";

       The on method works just like the "since" method, below, except it returns a list of messages whose
       internal system dates are the same as the date supplied as the argument.

   parse_headers
       Example:

         my $hashref = $imap->parse_headers( $msg || \@msgs, "Date", "Subject" )
           or die "Could not parse_headers: $@\n";

       The parse_headers method accepts as arguments a message sequence number and a list of header fields.  It
       returns a hash reference in which the keys are the header field names (without the colon) and the values
       are references to arrays of values.  On failure <undef> is returned and "LastError" is set.

       A picture would look something like this:

         $hashref = $imap->parse_headers( 1, "Date", "Received", "Subject", "To");
         $hashref = {
             "Date"     => [ "Thu, 09 Sep 1999 09:49:04 -0400" ]  ,
             "Received" => [ q/
               from mailhub ([111.11.111.111]) by mailhost.bigco.com
               (Netscape Messaging Server 3.6)  with ESMTP id AAA527D for
               <bigshot@bigco.com>; Fri, 18 Jun 1999 16:29:07 +0000
               /, q/
               from directory-daemon by mailhub.bigco.com (PMDF V5.2-31 #38473)
               id <0FDJ0010174HF7@mailhub.bigco.com> for bigshot@bigco.com
               (ORCPT rfc822;big.shot@bigco.com); Fri, 18 Jun 1999 16:29:05 +0000 (GMT)
               /, q/
               from someplace ([999.9.99.99]) by smtp-relay.bigco.com (PMDF V5.2-31 #38473)
               with ESMTP id <0FDJ0000P74H0W@smtp-relay.bigco.com> for big.shot@bigco.com; Fri,
               18 Jun 1999 16:29:05 +0000 (GMT)
               /] ,
             "Subject" => [ qw/ Help! I've fallen and I can't get up!/ ] ,
             "To"      => [ "Big Shot <big.shot@bigco.com> ] ,
         };

       The text in the example for the "Received" array has been formatted to make reading the example easier.
       The actual values returned are just strings of words separated by spaces and with newlines and carriage
       returns stripped off.  The Received header is probably the main reason that the parse_headers method
       creates a hash of lists rather than a hash of values.

       If the second argument to parse_headers is 'ALL' or if it is unspecified then all available headers are
       included in the returned hash of lists.

       If you're not emotionally prepared to deal with a hash of lists then you can always call the "fetch"
       method yourself with the appropriate parameters and parse the data out any way you want to.  Also, in the
       case of headers whose contents are also reflected in the envelope, you can use the "get_envelope" method
       as an alternative to "parse_headers".

       If the "Uid" parameter is true then the first argument will be treated as a message UID.  If the first
       argument is a reference to an array of message sequence numbers (or UID's if "Uid" is true), then
       parse_headers will be run against each message in the array.  In this case the return value is a hash, in
       which the key is the message sequence number (or UID) and the value is a reference to a hash as described
       above.

       An example of using parse_headers to print the date and subject of every message in your demo folder
       could look like this:

         use Mail::IMAPClient;
         my $imap = Mail::IMAPClient->new(
             Server => $imaphost, User => $login, Password => $pass, Uid => 1
         );

         $imap->select("demo");

         my $msgs = $imap->search("ALL");
         for my $h (

          # get the Subject and Date from every message in folder "demo" the
          # first arg is a reference to an array listing all messages in the
          # folder (which is what gets returned by the $imap->search("ALL")
          # method when called in scalar context) and the remaining arguments
          # are the fields to parse out The key is the message number, which
          # in this case we don't care about:

           values %{ $imap->parse_headers( $msgs , "Subject", "Date") } )
         {
             # $h is the value of each element in the hash ref returned
             # from parse_headers, and $h is also a reference to a hash.
             # We'll only print the first occurrence of each field because
             # we don't expect more than one Date: or Subject: line per
             # message.
             print map { "$_:\t$h->{$_}[0]\n"} keys %$h;
         }

   recent
       Example:

         my @recent = $imap->recent or warn "No recent msgs: $@\n";

       The recent method performs an IMAP SEARCH RECENT search against the selected folder and returns an array
       of sequence numbers (or UID's, if the "Uid" parameter is true) of messages that are recent.

   recent_count
       Example:

         my $count = 0;
         defined($count = $imap->recent_count($folder))
           or die "recent_count failed: $@\n";

       The recent_count method accepts as an argument a folder name.  It returns the number of recent messages
       in the folder (as returned by the IMAP client command "STATUS folder RECENT"), or "undef" in the case of
       an error.  The recent_count method was contributed by Rob Deker (deker@ikimbo.com).

   noop
       Example:

         $imap->noop or die "noop failed: $@\n";

       The noop method performs an IMAP NOOP command.  Per RFC3501 this command does nothing and always
       succeeds.  However, if a connection times out or other errors occur while communicating with the server,
       this method can still fail.  This command can be used as a periodic poll to check for (untagged) status
       updates (new messages, etc.) from the server and also to reset any inactivity/auto-logout timers the
       server may maintain.

   reconnect
       Example:

         $imap->noop or $imap->reconnect or die "noop failed: $@\n";

       Attempt to reconnect if the IMAP connection unless $imap is already in the IsConnected state.  This
       method calls "connect" and optionally "select" if a Folder was previously selected.  On success, returns
       the (same) $imap object.  On failure <undef> is returned and "LastError" is set.

       Version note: method added in Mail::IMAPClient 3.17

   rename
       Example:

         $imap->rename( $oldname, $nedwname )
           or die "rename failed: $@\n";

       The rename method accepts two arguments: the name of an existing folder, and a new name for the folder.
       The existing folder will be renamed to the new name using the RENAME IMAP client command.  rename will
       return a true value if successful, or "undef" if unsuccessful.

   restore_message
       Example:

         $imap->restore_message(@msgs) or die "restore_message failed: $@\n";

       The restore_message method is used to undo a previous "delete_message" operation (but not if there has
       been an intervening "expunge" or "close").  The IMAPClient object must be in "Selected" status to use the
       restore_message method.

       The restore_message method accepts a list of arguments.  If the "Uid" parameter is not set to a true
       value, then each item in the list should be either:

       >   a message sequence number,

       >   a comma-separated list of message sequence numbers,

       >   a reference to an array of message sequence numbers, or

       If the "Uid" parameter is set to a true value, then each item in the list should be either:

       >   a message UID,

       >   a comma-separated list of UID's, or

       >   a reference to an array of message UID's.

       The messages identified by the sequence numbers or UID's will have their \Deleted flags cleared,
       effectively "undeleting" the messages.  restore_message returns the number of messages it was able to
       restore.

       Note that restore_messages is similar to calling ""unset_flag"("\Deleted",@msgs)", except that
       restore_messages returns a (slightly) more meaningful value. Also it's easier to type.

   run
       Example:

         $imap->run(@args) or die "run failed: $@\n";

       The run method is provided to make those uncommon things possible... however, we would like you to
       contribute the knowledge of missing features with us.

       The run method excepts one or two arguments.  The first argument is a string containing an IMAP client
       command, including a tag and all required arguments.  The optional second argument is a string to look
       for that will indicate success.  (The default is "/OK.*/").  The run method returns an array (or arrayref
       in scalar context) of output lines from the command, which you are free to parse as you see fit.

       The run method does not do any syntax checking, other than rudimentary checking for a tag.

       When run processes the command, it increments the transaction count and saves the command and responses
       in the History buffer in the same way other commands do.  However, it also creates a special entry in the
       History buffer named after the tag supplied in the string passed as the first argument.  If you supply a
       numeric value as the tag then you may risk overwriting a previous transaction's entry in the History
       buffer.

       If you want the control of run but you don't want to worry about tags then see "tag_and_run", below.

   search
       Example:

         my $msgs1 = $imap->search(@args);
         if ($msgs1) {
             print "search matches: @$msgs1";
         }
         else {
             warn "Error in search: $@\n" if $@;
         }

         # or  note: be sure to quote string properly
         my $msgs2 = $imap->search( \( $imap->Quote($msgid), "FROM", q{"me"} ) )
           or warn "search failed: $@\n";

         # or  note: be sure to quote string properly
         my $msgs3 = $imap->search('TEXT "string not in mailbox"')
           or warn "search failed: $@\n";

       The search method implements the SEARCH IMAP client command.  Any arguments supplied to search are
       prefixed with a space then appended to the SEARCH IMAP client command.  The SEARCH IMAP client command
       allows for many options and arguments.  See RFC3501 for details.

       As of version 3.17 search tries to "DWIM" by automatically quoting things that likely need quotes when
       the words do not match any of the following:

           ALL ANSWERED BCC BEFORE BODY CC DELETED DRAFT FLAGGED
           FROM HEADER KEYWORD LARGER NEW NOT OLD ON OR RECENT
           SEEN SENTBEFORE SENTON SENTSINCE SINCE SMALLER SUBJECT
           TEXT TO UID UNANSWERED UNDELETED UNDRAFT UNFLAGGED
           UNKEYWORD UNSEEN

       The following options exist to avoid the automatic quoting (note: caller is responsible for verifying the
       data sent in these cases is properly escaped/quoted):

       •   specify a single string/argument in the call to search.

       •   specify args as scalar references (SCALAR) and the values of those SCALAR refs will be passed along
           as-is.

       The search method returns an array containing sequence numbers of messages that passed the SEARCH IMAP
       client command's search criteria.  If the "Uid" parameter is true then the array will contain message
       UID's.  If search is called in scalar context then a pointer to the array will be passed, instead of the
       array itself.  If no messages meet the criteria then search returns an empty list (when in list context)
       or "undef" (in scalar context).

       Since a valid, successful search can legitimately return zero matches, you may wish to distinguish
       between a search that correctly returns zero hits and a search that has failed for some other reason
       (i.e.  invalid search parameters).  Therefore, the $@ variable will always be cleared before the SEARCH
       command is issued to the server, and will thus remain empty unless the server gives a BAD or NO response
       to the SEARCH command.

   see
       Example:

         $imap->see(@msgs) or die "see failed: $@\n";

       The see method accepts a list of one or more messages sequence numbers, or a single reference to an array
       of one or more message sequence numbers, as its argument(s).  It then sets the \Seen flag for those
       message(s).  Of course, if the "Uid" parameter is set to a true value then those message sequence numbers
       had better be unique message id's, but then you already knew that, didn't you?

       Note that specifying "$imap->see(@msgs)" is just a shortcut for specifying
       "$imap->"set_flag"("Seen",@msgs)".

   seen
       Example:

         my @seenMsgs = $imap->seen or warn "No seen msgs: $@\n";

       The seen method performs an IMAP SEARCH SEEN search against the selected folder and returns an array of
       sequence numbers of messages that have already been seen (ie their \Seen flag is set).  If the "Uid"
       parameter is true then an array of message UID's will be returned instead.  If called in scalar context
       than a reference to the array (rather than the array itself) will be returned.

   select
       Example:

         $imap->select($folder) or die "select failed: $@\n";

       The select method selects a folder and changes the object's state to Selected.  It accepts one argument,
       which is the name of the folder to select.

   selectable
       Example:

         foreach my $f ( grep( $imap->selectable($_), $imap->folders ) ) {
             $imap->select($f);
         }

       The selectable method accepts one value, a folder name, and returns true if the folder is selectable or
       false if it is not selectable.

   sentbefore
       Example:

         my @msgs = $imap->sentbefore($Rfc3501_date)
           or warn "Could not find any msgs sent before $Rfc3501_date: $@\n";

       The sentbefore method works just like "sentsince", below, except it searches for messages that were sent
       before the date supplied as an argument to the method.

   senton
       Example:

         my @msgs = $imap->senton($Rfc3501_date)
           or warn "Could not find any messages sent on $Rfc3501_date: $@\n";

       The senton method works just like "sentsince", below, except it searches for messages that were sent on
       the exact date supplied as an argument to the method.

   sentsince
       Example:

         my @msgs = $imap->sentsince($Rfc3501_date)
           or warn "Could not find any messages sent since $Rfc3501_date: $@\n";

       The sentsince method accepts one argument, a date in either epoch time format (seconds since 1/1/1970, or
       as output by time and as accepted by localtime) or in the date_text format as defined in RFC3501 (dd-Mon-
       yyyy, where Mon is the English-language three-letter abbreviation for the month).

       It searches for items in the currently selected folder for messages sent since the day whose date is
       provided as the argument.  It uses the RFC822 Date: header to determine the sentsince date.  (Actually,
       it the server that uses the Date: header; this documentation just assumes that the date is coming from
       the Date: header because that's what RFC3501 dictates.)

       In the case of arguments supplied as a number of seconds, the returned result list will include items
       sent on or after that day, regardless of whether they arrived before the specified time on that day.  The
       IMAP protocol does not support searches at a granularity finer than a day, so neither do I.  On the other
       hand, the only thing I check for in a date_text argument is that it matches the pattern
       "/\d\d-\D\D\D-\d\d\d\d/" (notice the lack of anchors), so if your server lets you add something extra to
       a date_text string then so will Mail::IMAPClient.

       If you'd like, you can use the "Rfc3501_date" method to convert from epoch time (as returned by time)
       into an RFC3501 date specification.

   separator
       Example:

         my $sepChar = $imap->separator(@args)
           or die "Could not get separator: $@\n";

       The separator method returns the character used as a separator character in folder hierarchies.  On UNIX-
       based servers, this is often but not necessarily a forward slash (/).  It accepts one argument, the name
       of a folder whose hierarchy's separator should be returned.  If no folder name is supplied then the
       separator for the INBOX is returned, which probably is good enough.

       If you want your programs to be portable from IMAP server brand X to IMAP server brand Y, then you should
       never use hard-coded separator characters to specify subfolders.  (In fact, it's even more complicated
       than that, since some server don't allow any subfolders at all, some only allow subfolders under the
       "INBOX" folder, and some forbid subfolders in the inbox but allow them "next" to the inbox.  Furthermore,
       some server implementations do not allow folders to contain both subfolders and mail messages; other
       servers allow this.)

   set_flag
       Example:

         $imap->set_flag( "Seen", @msgs )
           or die "Could not set flag: $@\n";

       The set_flag method accepts the name of a flag as its first argument and a list of one or more messages
       sequence numbers, or a single reference to an array of one or more message sequence numbers, as its next
       argument(s).  It then sets the flag specified for those message(s).  Of course, if the "Uid" parameter is
       set to a true value then those message sequence numbers had better be unique message id's, just as you'd
       expect.

       Note that when specifying the flag in question, the preceding backslash (\) is entirely optional.  (For
       you, that is.  Mail::IMAPClient still has remember to stick it in there before passing the command to the
       server if the flag is one of the reserved flags specified in RFC3501.  This is in fact so important that
       the method checks its argument and adds the backslash when necessary, which is why you don't have to
       worry about it overly much.)

   setacl
       Example:

         $imap->setacl( $folder, $userid, $aclstring )
           or die "Could not set acl: $@\n";

       The setacl method accepts three input arguments, a folder name, a user id (or authentication identifier,
       to use the terminology of RFC2086), and an access rights modification string.  See RFC2086 for more
       information.  (This is somewhat experimental and its implementation may change.)

   since
       Example:

         my @msgs = $imap->since($date)
           or warn "Could not find any messages since $date: $@\n";

       The since method accepts a date in either epoch format (seconds since 1/1/1970, or as output by "time" in
       perlfunc and as accepted by "localtime" in perlfunc) or in the date_text format as defined in RFC3501
       (dd-Mon-yyyy, where Mon is the English-language three-letter abbreviation for the month).  It searches
       for items in the currently selected folder for messages whose internal dates are on or after the day
       whose date is provided as the argument.  It uses the internal system date for a message to determine if
       that message was sent since the given date.

       In the case of arguments supplied as a number of seconds, the returned result list will include items
       whose internal date is on or after that day, regardless of whether they arrived before the specified time
       on that day.

       If since is called in a list context then it will return a list of messages meeting the SEARCH SINCE
       criterion, or an empty list if no messages meet the criterion.

       If since is called in a scalar context then it will return a reference to an array of messages meeting
       the SEARCH SINCE criterion, or "undef" if no messages meet the criterion.

       Since since is a front-end to "search", some of the same rules apply.  For example, the $@ variable will
       always be cleared before the SEARCH command is issued to the server, and will thus remain empty unless
       the server gives a BAD or NO response to the SEARCH command.

   size
       Example:

         my $size = $imap->size($msgId)
           or die "Could not find size of message $msgId: $@\n";

       The size method accepts one input argument, a sequence number (or message UID if the "Uid" parameter is
       true).  It returns the size of the message in the currently selected folder with the supplied sequence
       number (or UID).  The IMAPClient object must be in a Selected state in order to use this method.

   sort
       Example:

         my @msgs = $imap->sort(@args);
         warn "Error in sort: $@\n" if $@;

       The sort method is just like the "search" method, only different.  It implements the SORT extension as
       described in https://tools.ietf.org/html/rfc5256.  It would be wise to use the "has_capability" method to
       verify that the SORT capability is available on your server before trying to use the sort method.  If you
       forget to check and you're connecting to a server that doesn't have the SORT capability then sort will
       return undef.  "LastError" will then say you are "BAD".  If your server doesn't support the SORT
       capability then you'll have to use "search" and then sort the results yourself.

       The first argument to sort is a space-delimited list of sorting criteria.  The Internet Draft that
       describes SORT requires that this list be wrapped in parentheses, even if there is only one sort
       criterion.  If you forget the parentheses then the sort method will add them.  But you have to forget
       both of them, or none.  This isn't CMS running under VM!

       The second argument is a character set to use for sorting.  Different character sets use different
       sorting orders, so this argument is important.  Since all servers must support UTF-8 and US-ASCII if they
       support the SORT capability at all, you can use one of those if you don't have some other preferred
       character set in mind.

       The rest of the arguments are searching criteria, just as you would supply to the "search" method.  These
       are all documented in RFC3501.  If you just want all of the messages in the currently selected folder
       returned to you in sorted order, use ALL as your only search criterion.

       The sort method returns an array containing sequence numbers of messages that passed the SORT IMAP client
       command's search criteria.  If the "Uid" parameter is true then the array will contain message UID's.  If
       sort is called in scalar context then a pointer to the array will be passed, instead of the array itself.
       The message sequence numbers or unique identifiers are ordered according to the sort criteria specified.
       The sort criteria are nested in the order specified; that is, items are sorted first by the first
       criterion, and within the first criterion they are sorted by the second criterion, and so on.

       The sort method will clear $@ before attempting the SORT operation just as the "search" method does.

   starttls
       Example:

         $imap->starttls() or die "starttls failed: $@\n";

       The starttls method accepts no arguments.  This method is used to upgrade an exiting connection which is
       not authenticated to a TLS/SSL connection by using the IMAP STARTTLS command followed by using the
       start_SSL class method from IO::Socket::SSL to do the necessary TLS negotiation.  The negotiation is done
       in a blocking fashion with a default Timeout of 30 seconds.  The arguments used in the call to start_SSL
       can be controlled by setting the Mail::IMAPClient "Starttls" attribute to an ARRAY reference containing
       the desired arguments.

       Version note: method added in Mail::IMAPClient 3.22

   status
       Example:

         my @rawdata = $imap->status( $folder, qw/(Messages)/ )
           or die "Error obtaining status: $@\n";

       The status method accepts one argument, the name of a folder (or mailbox, to use RFC3501's terminology),
       and returns an array containing the results of running the IMAP STATUS client command against that
       folder.  If additional arguments are supplied then they are appended to the IMAP STATUS client command
       string, separated from the rest of the string and each other with spaces.

       If status is not called in an array context then it returns a reference to an array rather than the array
       itself.

       The status method should not be confused with the Status method (with an uppercase 'S'), which returns
       information about the IMAPClient object.  (See the section labeled "Status Methods", below).

   store
       Example:

         $imap->store(@args) or die "Could not store: $@\n";

       The store method accepts a message sequence number or comma-separated list of message sequence numbers as
       a first argument, a message data item name, and a value for the message data item.  Currently, data items
       are the word "FLAGS" followed by a space and a list of flags (in parens).  The word "FLAGS" can be
       modified by prefixing it with either a "+" or a "-" (to indicate "add these flags" or "remove these
       flags") and by suffixing it with ".SILENT" (which reduces the amount of output from the server; very
       useful with large message sets).  Normally you won't need to call store because there are oodles of
       methods that will invoke store for you with the correct arguments.  Furthermore, these methods are
       friendlier and more flexible with regards to how you specify your arguments.  See for example "see",
       "deny_seeing", "delete_message", and "restore_message".  Or "mark", "unmark", "set_flag", and
       "unset_flag".

   subject
       Example:

         my $subject = $imap->subject($msg);

       The subject method accepts one argument, a message sequence number (or a message UID, if the Uid
       parameter is true).  The text in the "Subject" header of that message is returned (without the "Subject:
       " prefix).  This method is a short-cut for:

         my $subject = $imap->get_header($msg, "Subject");

   subscribed
       Example:

         my @subscribedFolders = $imap->subscribed
           or warn "Could not find subscribed folders: $@\n";

       The subscribed method works like the folders method, above, except that the returned list (or array
       reference, if called in scalar context) contains only the subscribed folders.

       Like "folders", you can optionally provide a prefix argument to the subscribed method.

   tag_and_run
       Example:

         my $output = $imap->tag_and_run(@args)
           or die "Could not tag_and_run: $@\n";

       The tag_and_run method accepts one or two arguments.  The first argument is a string containing an IMAP
       client command, without a tag but with all required arguments.  The optional second argument is a string
       to look for that will indicate success (without pattern delimiters).  The default is "OK.*".

       The tag_and_run method will prefix your string (from the first argument) with the next transaction number
       and run the command.  It returns an array of output lines from the command, which you are free to parse
       as you see fit.  Using this method instead of run (above) will free you from having to worry about
       handling the tags (and from worrying about the side affects of naming your own tags).

   uidexpunge
       Example:

         $imap->uidexpunge(@uids) or die "Could not uidexpunge: $@\n";

       The uidexpunge method implements the UID EXPUNGE IMAP (RFC4315 UIDPLUS ext) client command to permanently
       remove all messages that have the \Deleted flag set and have a UID that is included in the list of UIDs.

       uidexpunge returns an array or arrayref (scalar context) of output lines returned from the UID EXPUNGE
       command.

       uidexpunge returns undef on failure.

       If the server does not support the UIDPLUS extension, this method returns undef.

   uidnext
       Example:

         my $nextUid = $imap->uidnext($folder) or die "uidnext failed: $@\n";

       The uidnext method accepts one argument, the name of a folder, and returns the numeric string that is the
       next available message UID for that folder.

   thread
       Example:

         my $thread = $imap->thread( $algorithm, $charset, @search_args );

       The thread method accepts zero to three arguments.  The first argument is the threading algorithm to use,
       generally either ORDEREDSUBJECT or REFERENCES.  The second argument is the character set to use, and the
       third argument is the set of search arguments to use.

       If the algorithm is not supplied, it defaults to REFERENCES if available, or ORDEREDSUBJECT if available.
       If neither of these is available then the thread method returns undef.

       If the character set is not specified it will default to UTF-8.

       If the search arguments are not specified, the default is ALL.

       If thread is called for an object connected to a server that does not support the THREADS extension then
       the thread method will return "undef".

       The threads method will issue the THREAD command as defined in https://tools.ietf.org/html/rfc5256.  It
       returns an array of threads.  Each element in the array is either a message id or a reference to another
       array of (sub)threads.

       If the "Uid" parameter is set to a true value then the message id's returned in the thread structure will
       be message UID's.  Otherwise they will be message sequence numbers.

   uidvalidity
       Example:

         my $validity = $imap->uidvalidity($folder)
           or die "uidvalidity failed: $@\n";

       The uidvalidity method accepts one argument, the name of a folder, and returns the numeric string that is
       the unique identifier validity value for the folder.

   unmark
       Example:

         $imap->unmark(@msgs) or die "Could not unmark: $@\n";

       The unmark method accepts a list of one or more messages sequence numbers, or a single reference to an
       array of one or more message sequence numbers, as its argument(s).  It then unsets the \Flagged flag for
       those message(s).  Of course, if the "Uid" parameter is set to a true value then those message sequence
       numbers should really be unique message id's.

       Note that specifying "$imap->unmark(@msgs)" is just a shortcut for specifying
       "$imap->unset_flag("Flagged",@msgs)".

       Note also that the \Flagged flag is just one of many possible flags.  This is a little confusing, but
       you'll have to get used to the idea that among the reserved flags specified in RFC3501 is one name
       \Flagged.  There is no specific meaning for this flag; it means whatever the mailbox owner (or delegate)
       wants it to mean when it is turned on.

   unseen
       Example:

         my @unread = $imap->unseen or warn "Could not find unseen msgs: $@\n";

       The unseen method performs an IMAP SEARCH UNSEEN search against the selected folder and returns an array
       of sequence numbers of messages that have not yet been seen (ie their \Seen flag is not set).  If the
       "Uid" parameter is true then an array of message UID's will be returned instead.  If called in scalar
       context than a pointer to the array (rather than the array itself) will be returned.

   unseen_count
       Example:

         foreach my $f ($imap->folders) {
             print "The $f folder has ",
               $imap->unseen_count($f)||0, " unseen messages.\n";
         }

       The unseen_count method accepts the name of a folder as an argument and returns the number of unseen
       messages in that folder.  If no folder argument is provided then it returns the number of unseen messages
       in the currently selected Folder.

   unset_flag
       Example:

         $imap->unset_flag( "\Seen", @msgs )
           or die "unset_flag failed: $@\n";

       The unset_flag method accepts the name of a flag as its first argument and a list of one or more messages
       sequence numbers, or a single reference to an array of one or more message sequence numbers, as its next
       argument(s).  It then unsets the flag specified for those message(s).  Of course, if the "Uid" parameter
       is set to a true value then those message sequence numbers had better be unique message id's, just as
       you'd expect.

Other IMAP Client Commands

       Until release 2.99, when you called a method which did not exist, they where automatically translated
       into an IMAP call with the same name via an AUTOLOAD hack.  This "feature" was removed for various
       reasons: people made typos in the capitalization of method names, and the program still seemed to work
       correctly.  Besides, it blocked further development of this module, because people did not contribute
       their private extensions to the protocol implementation.

   copy($msg, $folder)
       Copy a message from the currently selected folder in the folder whose name is in $folder

   subscribe($folder)
       Subscribe to a folder

       CAUTION: Once again, remember to quote your quotes (or use the "Quote" method) if you want quotes to be
       part of the IMAP command string.

       You can also use the default method to override the behavior of implemented IMAP methods by changing the
       case of the method name, preferably to all-uppercase so as not to conflict with the Class method and
       accessor method namespace.  For example, if you don't want the "search" method's behavior (which returns
       a list of message numbers) but would rather have an array of raw data returned from your "search"
       operation, you can issue the following snippet:

         my @raw = $imap->SEARCH("SUBJECT","Whatever...");

       which is slightly more efficient than the equivalent:

         $imap->search("SUBJECT","Whatever...");
         my @raw = $imap->Results;

       Of course you probably want the search results tucked nicely into a list for you anyway, in which case
       you might as well use the "search" method.

Parameters

       There are several parameters that influence the behavior of an IMAPClient object.  Each is set by
       specifying a named value pair during new method invocation as follows:

         my $imap = Mail::IMAPClient->new ( parameter  => "value",
             parameter2 => "value",
             ...
         );

       Parameters can also be set after an object has been instantiated by using the parameter's eponymous
       accessor method like this:

         my $imap = Mail::IMAPClient->new;
            $imap->parameter( "value");
            $imap->parameter2("value");

       The eponymous accessor methods can also be used without arguments to obtain the current value of the
       parameter as follows:

         my $imap = Mail::IMAPClient->new;
            $imap->parameter( "value");
            $imap->parameter2("value");

           ...    # A whole bunch of awesome Perl code, omitted for brevity

         my $forgot  = $imap->parameter;
         my $forgot2 = $imap->parameter2;

       Note that in these examples I'm using 'parameter' and 'parameter2' as generic parameter names.  The
       IMAPClient object doesn't actually have parameters named 'parameter' and 'parameter2'.  On the contrary,
       the available parameters are:

   Authmechanism
       Example:

         $imap->Authmechanism("CRAM-MD5");
         # or
         my $authmech = $imap->Authmechanism();

       If specified, the Authmechanism causes the specified authentication mechanism to be used whenever
       Mail::IMAPClient would otherwise invoke login.  If the value specified for the Authmechanism parameter is
       not a valid authentication mechanism for your server then you will never ever be able to log in again for
       the rest of your Perl script, probably.  So you might want to check, like this:

         my $authmech = "CRAM-MD5";
         $imap->has_capability($authmech) and $imap->Authmechanism($authmech);

       Of course if you know your server supports your favorite authentication mechanism then you know, so you
       can then include your Authmechanism with your new call, as in:

         my $imap = Mail::IMAPClient->new(
             User    => $user,
             Passord => $passord,
             Server  => $server,
             Authmechanism  => $authmech,
             %etc
         );

       If Authmechanism is supplied but Authcallback is not then you had better be supporting one of the
       authentication mechanisms that Mail::IMAPClient supports "out of the box" (such as CRAM-MD5).

   Authcallback
       Example:

         $imap->Authcallback( \&callback );

       This specifies a default callback to the default authentication mechanism (see "Authmechanism", above).
       Together, these two methods replace automatic calls to login with automatic calls that look like this
       (sort of):

         $imap->authenticate($imap->Authmechanism,$imap->Authcallback);

       If Authmechanism is supplied but Authcallback is not then you had better be supporting one of the
       authentication mechanisms that Mail::IMAPClient supports "out of the box" (such as CRAM-MD5).

   Authuser
       The Authuser parameter is used by the DIGEST-MD5 "Authmechanism".

       Typically when you authenticate the username specified in the User parameter is used.  However, when
       using the DIGEST-MD5 Authmechanism the Authuser can be used to specify a different username for the
       login.

       This can be useful to mark messages as seen for the Authuser if you don't know the password of the user
       as the seen state is often a per-user state.

   Buffer
       Example:

         $Buffer = $imap->Buffer();
         # or:
         $imap->Buffer($new_value);

       The Buffer parameter sets the size of a block of I/O.  It is ignored unless "Fast_io", below, is set to a
       true value (the default), or unless you are using the "migrate" method.  It's value should be the number
       of bytes to attempt to read in one I/O operation.  The default value is 4096.

       When using the "migrate" method, you can often achieve dramatic improvements in throughput by adjusting
       this number upward.  However, doing so also entails a memory cost, so if set too high you risk losing all
       the benefits of the "migrate" method's chunking algorithm.  Your program can thus terminate with an "out
       of memory" error and you'll have no one but yourself to blame.

       Note that, as hinted above, the Buffer parameter affects the behavior of the "migrate" method regardless
       of whether you have "Fast_io" turned on.  Believe me, you don't want to go around migrating tons of mail
       without using buffered I/O!

   Clear
       Example:

         $Clear = $imap->Clear();
         # or:
         $imap->Clear($integer);

       The name of this parameter, for historical reasons, is somewhat misleading.  It should be named Wrap,
       because it specifies how many transactions are stored in the wrapped history buffer.  But it didn't
       always work that way; the buffer used to actually get cleared.  The name though remains the same in the
       interests of backwards compatibility.

       Clear specifies that the object's history buffer should be wrapped after every n transactions, where n is
       the value specified for the Clear parameter.  Calling the eponymous Clear method without an argument will
       return the current value of the Clear parameter but will not cause clear the history buffer to wrap.

       Setting Clear to 0 turns off automatic history buffer wrapping, and setting it to 1 turns off the history
       buffer facility (except for the last transaction, which cannot be disabled without breaking the
       IMAPClient module).  Setting Clear to 0 will not cause an immediate clearing of the history buffer;
       setting it to 1 (or any other number) will (except of course for that inevitable last transaction).

       The default Clear value is set to five (5) in order to conserve memory.

   Compress
       If set, Mail::IMAPClient attempts to enable use of the RFC4978 COMPRESS DEFLATE extension.  This requires
       that the server supports this CAPABILITY.  This attribute can be set to a true value to enable or an
       ARRAYREF to control the arguments used in the call to Compress::Zlib::deflateInit().

       Mail::IMAPClient will automatically use Compress::Zlib to deflate/inflate the data to/from the server.
       This attribute is used in the "login" method.

       See also "compress" and "capability".

       Version note: attribute added in Mail::IMAPClient 3.30

   Debug
       Example:

         $Debug = $imap->Debug();
         # or:
         $imap->Debug($true_or_false);

       Sets the debugging flag to either a true or false value.  Can be supplied with the "new" method call or
       separately by calling the Debug object method.  Use of this parameter is strongly recommended when
       debugging scripts and required when reporting bugs.

   Debug_fh
       Example:

         $Debug_fh = $imap->Debug_fh();
         # or:
         $imap->Debug_fh($fileHandle);

       Specifies the file handle to which debugging information should be printed.  It can either a file handle
       object reference or a file handle glob.  The default is to print debugging info to STDERR.

       For example, you can:

         use Mail::IMAPClient;
         use IO::File;
         # set $user, $pass, and $server here
         my $dh = IO::File->new(">debugging.output")
           or die "Can't open debugging.output: $!\n";
         my $imap = Mail::IMAPClient->new(
             User=>$user, Password=>$pass, Server=>$server, Debug=>1, Debug_fh => $dh
         );

       which is the same as:

         use Mail::IMAPClient;
         use IO::File;
         # set $user, $pass, and $server here
         my $imap = Mail::IMAPClient->new(
             User     => $user,
             Password => $pass,
             Server   => $server,
             Debug    => "yes, please",
             Debug_fh => IO::File->new(">debugging.output")
               || die "Can't open debugging.output: $!\n"
         );

       You can also:

         use Mail::IMAPClient;
         # set $user, $pass, and $server here
         open(DBG,">debugging.output")
           or die "Can't open debugging.output: $!\n";
         my $imap = Mail::IMAPClient->new(
           User=>$user, Password=>$pass, Server=>$server, Debug=> 1, Debug_fh => *DBG
         );

       Specifying this parameter is not very useful unless "Debug" is set to a true value.

   Domain
       The Domain parameter is used by the NTLM "Authmechanism".  The domain is an optional parameter for NTLM
       authentication.

   EnableServerResponseInLiteral
       Removed in 2.99_01 (now autodetect)

   Fast_io
       Example:

         $Fast_io = $imap->Fast_io();
         # or:
         $imap->Fast_io($true_or_false);

       The Fast_io parameter controls whether or not the Mail::IMAPClient object will attempt to use non-
       blocking I/O on the IMAP socket.  It is turned on by default (unless the caller provides the socket to be
       used).

       See also "Buffer".

   Folder
       Example:

         $Folder = $imap->Folder();
         # or:
         $imap->Folder($new_value);

       The Folder parameter returns the name of the currently-selected folder (in case you forgot).  It can also
       be used to set the name of the currently selected folder, which is completely unnecessary if you used the
       "select" method (or "select"'s read-only equivalent, the "examine" method) to select it.

       Note that setting the Folder parameter does not automatically select a new folder; you use the "select"
       or "examine" object methods for that.  Generally, the Folder parameter should only be queried (by using
       the no-argument form of the Folder method).  You will only need to set the Folder parameter if you use
       some mysterious technique of your own for selecting a folder, which you probably won't do.

   Ignoresizeerrors
       Certain (caching) servers, like Exchange 2007, often report the wrong message size.  Instead of chopping
       the message into a size that it fits the specified size, the reported size will be simply ignored when
       this parameter is set to 1.

   Keepalive
       Some firewalls and network gear like to timeout connections prematurely if the connection sits idle.  The
       Keepalive parameter, when set to a true value, affects the behavior of "new" and "Socket" by enabling
       SO_KEEPALIVE on the socket.

       Version note: attribute added in Mail::IMAPClient 3.17

   Maxcommandlength
       The Maxcommandlength attribute is used by fetch() to limit length of commands sent to a server.  The
       default is 1000 chars, following the recommendation of RFC2683 section 3.2.1.5.

       Note: this attribute should also be used for several other methods but this has not yet been implemented
       please feel free to file bugs for methods where you run into problems with this.

       This attribute should remove the need for utilities like imapsync to create their own split() functions
       and instead allows Mail::IMAPClient to DWIM.

       In practice, this parameter has proven to be useful to overcome a limit of 8000 octets for UW-IMAPD and
       16384 octets for Courier/Cyrus IMAP servers.

       Version note: attribute added in Mail::IMAPClient 3.17

   Maxtemperrors
       Example:

         $Maxtemperrors = $imap->Maxtemperrors();
         # or:
         $imap->Maxtemperrors($number);

       The Maxtemperrors parameter specifies the number of times a read or write operation is allowed to fail on
       a "Resource Temporarily Available" (e.g. EAGAIN) error.  The default setting is undef which means there
       is no limit.

       Setting this parameter to the string "unlimited" (instead of undef) to ignore "Resource Temporarily
       Unavailable" errors is deprecated.

       Note: This setting should be used with caution and may be removed in a future release.  Setting this can
       cause methods to return to the caller before data is received (and then handled) properly thereby
       possibly then leaving the module in a bad state.  In the future, this behavior may be changed in an
       attempt to avoid this situation.

   Password
       Example:

         $Password = $imap->Password();
         # or:
         $imap->Password($new_value);

       Specifies the password to use when logging into the IMAP service on the host specified in the Server
       parameter as the user specified in the User parameter.  Can be supplied with the new method call or
       separately by calling the Password object method.

       If Server, User, and Password are all provided to the "new" method, then the newly instantiated object
       will be connected to the host specified in Server (at either the port specified in Port or the default
       port 143) and then logged on as the user specified in the User parameter (using the password provided in
       the Password parameter).  See the discussion of the "new" method, below.

   Peek
       Example:

         $Peek = $imap->Peek();
         # or:
         $imap->Peek($true_or_false);

       Setting Peek to a true value will prevent the "body_string", "message_string" and "message_to_file"
       methods from automatically setting the \Seen flag.  Setting "Peek" to 0 (zero) will force "body_string",
       "message_string", "message_to_file", and "parse_headers" to always set the \Seen flag.

       The default is to set the seen flag whenever you fetch the body of a message but not when you just fetch
       the headers.  Passing undef to the eponymous Peek method will reset the Peek parameter to its pristine,
       default state.

   Port
       Example:

         $Port = $imap->Port();
         # or:
         $imap->Port($new_value);

       Specifies the port on which the IMAP server is listening.  A default value of 993 (if "Ssl" is true) or
       143 is set during a call to "connect" if no value is provided by the caller.  This argument can be
       supplied with the "new" method call or separately by calling the "Port" object method.

   Prewritemethod
       Prewritemethod parameter should contain a reference to a subroutine that will do "special things" to data
       before it is sent to the IMAP server (such as encryption or signing).

       This method will be called immediately prior to sending an IMAP client command to the server.  Its first
       argument is a reference to the Mail::IMAPClient object and the second argument is a string containing the
       command that will be sent to the server.  Your Prewritemethod should return a string that has been signed
       or encrypted or whatever; this returned string is what will actually be sent to the server.

       Your Prewritemethod will probably need to know more than this to do whatever it does.  It is recommended
       that you tuck all other pertinent information into a hash, and store a reference to this hash somewhere
       where your method can get to it, possibly in the Mail::IMAPClient object itself.

       Note that this method should not actually send anything over the socket connection to the server; it
       merely converts data prior to sending.

       See also "Readmethod".

   Ranges
       Example:

         $imap->Ranges(1);
         # or:
         my $search = $imap->search(@search_args);
         if ( $imap->Ranges) { # $search is a MessageSet object
             print "This is my condensed search result: $search\n";
             print "This is every message in the search result: ",
               join(",",@$search),"\n;
         }

       If set to a true value, then the "search" method will return a Mail::IMAPClient::MessageSet object if
       called in a scalar context, instead of the array reference that fetch normally returns when called in a
       scalar context.  If set to zero or if undefined, then search will continue to return an array reference
       when called in scalar context.

       This parameter has no affect on the search method when search is called in a list context.

   RawSocket
       Example:
               $socket = $imap->RawSocket;
               # or:
               $imap->RawSocket($socketh);

       The RawSocket method can be used to obtain the socket handle of the current connection (say, to do I/O on
       the connection that is not otherwise supported by Mail::IMAPClient) or to replace the current socket with
       a new handle (for instance an SSL handle, see IO::Socket::SSL, but be sure to see the "Socket" method as
       well).

       If you supply a socket handle yourself, either by doing something like:

               $imap=Mail::IMAPClient->new(RawSocket => $sock, User => ... );

       or by doing something like:

               $imap = Mail::IMAPClient->new(User => $user,
                           Password => $pass, Server => $host);
               # blah blah blah
               $imap->RawSocket($ssl);

       then it will be up to you to establish the connection AND to authenticate, either via the "login" method,
       or the fancier "authenticate", or, since you know so much anyway, by just doing raw I/O against the
       socket until you're logged in.  If you do any of this then you should also set the "State" parameter
       yourself to reflect the current state of the object (i.e. Connected, Authenticated, etc).

       Note that no operation will be attempted on the socket when this method is called.  In particular, after
       the TCP connections towards the IMAP server is established, the protocol mandates the server to send an
       initial greeting message, and you will have to explicitly cope with this message before doing any other
       operation, e.g. trying to call "login". Caveat emptor.

       For a more DWIM approach to setting the socket see "Socket".

   Readmethod
       Example:

         $imap->Readmethod(   # IMAP, HANDLE, BUFFER, LENGTH, OFFSET
             sub {
                 my ( $self, $handle, $buffer, $count, $offset ) = @_;
                 my $rc = sysread( $handle, $$buffer, $count, $offset );
                 # do something useful here...
             }
         );

       Readmethod should contain a reference to a subroutine that will replace sysread.  The subroutine will be
       passed the following arguments: first the used Mail::IMAPClient object.  Second, a reference to a socket.
       Third, a reference to a scalar variable into which data is read (BUFFER). The data placed here should be
       "finished data", so if you are decrypting or removing signatures then be sure to do that before you place
       data into this buffer.  Fourth, the number of bytes requested to be read; the LENGTH of the request.
       Lastly, the OFFSET into the BUFFER where the data should be read.  If not supplied it should default to
       zero.

       Note that this method completely replaces reads from the connection to the server, so if you define one
       of these then your subroutine will have to actually do the read.  It is for things like this that we have
       the "Socket" parameter and eponymous accessor method.

       Your Readmethod will probably need to know more than this to do whatever it does.  It is recommended that
       you tuck all other pertinent information into a hash, and store a reference to this hash somewhere where
       your method can get to it, possibly in the Mail::IMAPClient object itself.

       See also "Prewritemethod".

   Readmoremethod
       Readmoremethod should contain a reference to a subroutine that will replace/enhance the behavior of the
       internal _read_more() method.  The subroutine will be passed the following arguments: first the used
       Mail::IMAPClient object.  Second, a reference to a socket.  Third, a timeout value which is used as the
       timeout value for CORE::select() by default.  Depending upon changes/features introduced by Readmethod
       changes may be required here.

       Version note: attribute added in Mail::IMAPClient 3.30

   Reconnectretry
       If an IMAP connection sits idle too long, the connection may be closed by the server or firewall, etc.
       The Reconnectretry parameter, when given a positive integer value, will cause Mail::IMAPClient to
       retrying IMAP commands up to X times when an EPIPE or ECONNRESET error occurs.  This is disabled (0) by
       default.

       See also "Keepalive"

       Version note: attribute added in Mail::IMAPClient 3.17

   Server
       Example:

         $Server = $imap->Server();
         # or:
         $imap->Server($hostname);

       Specifies the hostname or IP address of the host running the IMAP server.  If provided as part of the
       "new" method call, then the new IMAP object will automatically be connected at the time of instantiation.
       (See the "new" method, below.) Can be supplied with the "new" method call or separately by calling the
       Server object method.

   Showcredentials
       Normally debugging output will mask the login credentials when the plain text login mechanism is used.
       Setting Showcredentials to a true value will suppress this, so that you can see the string being passed
       back and forth during plain text login.  Only set this to true when you are debugging problems with the
       IMAP LOGIN command, and then turn it off right away when you're finished working on that problem.

       Example:

         print "This is very risky!\n" if $imap->Showcredentials();
         # or:
         $imap->Showcredentials(0);    # mask credentials again

   Socket
       PLEASE NOTE The semantics of this method has changed as of version 2.99_04 of this module.  If you need
       the old semantics use "RawSocket".

       Example:

         $Socket = $imap->Socket();
         # or:
         $imap->Socket($socket_fh);

       The Socket method can be used to obtain the socket handle of the current connection.  This may be
       necessary to do I/O on the connection that is not otherwise supported by Mail::IMAPClient) or to replace
       the current socket with a new handle (for instance an SSL handle, see IO::Socket::SSL).

       If you supply a socket handle yourself, either by doing something like:

         $imap = Mail::IMAPClient->new( Socket => $sock, User => ... );

       or by doing something like:

         $imap = Mail::IMAPClient->new(
           User => $user, Password => $pass, Server => $host
         );
         $imap->Socket($ssl);

       then you are responsible for establishing the connection, i.e. make sure that $ssl in the example is a
       valid and connected socket.

       This method is primarily used to provide a drop-in replacement for IO::Socket::(INET|IP), used by
       "connect" by default.  In fact, this method is called by "connect" itself after having established a
       suitable IO::Socket::(INET|IP) socket connection towards the target server; for this reason, this method
       also carries the normal operations associated with "connect", namely:

       •   read the initial greeting message from the server;

       •   call "login" if the conditions apply (see "connect" for details);

       •   leave the Mail::IMAPClient object in a suitable state.

       For these reasons, the following example will work "out of the box":

          use IO::Socket::SSL;
          my $imap = Mail::IMAPClient->new
           ( User     => 'your-username',
             Password => 'your-password',
             Socket   => IO::Socket::SSL->new
             (  Proto    => 'tcp',
                PeerAddr => 'some.imap.server',
                PeerPort => 993, # IMAP over SSL standard port
             ),
          );

       If you need more control over the socket, e.g. you have to implement a fancier authentication method, see
       "RawSocket".

   Starttls
       If an IMAP connection must start TLS/SSL after connecting to a server then set this attribute.  If the
       value is set to an arrayref then they will be used as arguments to IO::Socket::SSL->start_SSL.  By
       default this connection is set to blocking while establishing the connection with a timeout of 30
       seconds.  The socket will be reset to the original blocking/non-blocking value after a successful TLS
       negotiation has occurred.  The arguments used in the call to start_SSL can be controlled by setting this
       attribute to an ARRAY reference containing the desired arguments.

       Version note: attribute added in Mail::IMAPClient 3.22

   Socketargs
       The arguments used in the call to IO::Socket::{UNIX|INET|IP|SSL}->new can be controlled by setting this
       attribute to an ARRAY reference containing the desired arguments.

       For example, to always pass MultiHomed => 1 to IO::Socket::...->new the following can be used:

         $imap = Mail::IMAPClient->new(
           ..., Socketargs => [ MultiHomed => 1 ], ...
         );

       See also "Ssl" for specific control of the args to IO::Socket::SSL.

       Version note: attribute added in Mail::IMAPClient 3.34

   Ssl
       If an IMAP connection requires SSL you can set the Ssl attribute to '1' and Mail::IMAPClient will
       automatically use IO::Socket::SSL instead of IO::Socket::(INET|IP) to connect to the server.  This
       attribute is used in the "connect" method.  The arguments used in the call to IO::Socket::SSL->new can be
       controlled by setting this attribute to an ARRAY reference containing the desired arguments.

       See also "connect" for details on connection initiation and "Socket" and "Rawsocket" if you need to take
       more control of connection management.

       Version note: attribute added in Mail::IMAPClient 3.18

   Supportedflags
       Especially when "migrate()" is used, the receiving peer may need to be configured explicitly with the
       list of supported flags; that may be different from the source IMAP server.

       The names are to be specified as an ARRAY.  Black-slashes and casing will be ignored.

       You may also specify a CODE reference, which will be called for each of the flags separately.  In this
       case, the flags are not (yet) normalized.  The returned lists of the CODE calls are shape the resulting
       flag list.

   Timeout
       Example:

         $Timeout = $imap->Timeout();
         # or:
         $imap->Timeout($seconds);

       Specifies the timeout value in seconds for reads (default is 600).  Specifying a Timeout will prevent
       Mail::IMAPClient from blocking in a read.

       Since timeouts are implemented via the Perl select operator, the Timeout parameter may be set to a
       fractional number of seconds.  Setting Timeout to 0 (zero) disables the timeout feature.

   Uid
       Example:

         $Uid = $imap->Uid();
         # or:
         $imap->Uid($true_or_false);

       If "Uid" is set to a true value (i.e. 1) then the behavior of the "fetch", "search", "copy", and "store"
       methods (and their derivatives) is changed so that arguments that would otherwise be message sequence
       numbers are treated as message UID's and so that return values (in the case of the "search" method and
       its derivatives) that would normally be message sequence numbers are instead message UID's.

       Internally this is implemented as a switch that, if turned on, causes methods that would otherwise issue
       an IMAP FETCH, STORE, SEARCH, or COPY client command to instead issue UID FETCH, UID STORE, UID SEARCH,
       or UID COPY, respectively.  The main difference between message sequence numbers and message UID's is
       that, according to RFC3501, UID's must not change during a session and should not change between
       sessions, and must never be reused.  Sequence numbers do not have that same guarantee and in fact may be
       reused right away.

       Since folder names also have a unique identifier (UIDVALIDITY), which is provided when the folder is
       "select"ed or "examine"d or by doing something like "$imap->status($folder,"UIDVALIDITY"), it is possible
       to uniquely identify every message on the server, although normally you won't need to bother.

       The methods currently affected by turning on the "Uid" flag are:

         copy            fetch
         search          store
         message_string  message_uid
         body_string     flags
         move            size
         parse_headers   thread

       Note that if for some reason you only want the "Uid" parameter turned on for one command, then you can
       choose between the following two snippets, which are equivalent:

       Example 1:

         $imap->Uid(1);
         my @uids = $imap->search('SUBJECT',"Just a silly test"); #
         $imap->Uid(0);

       Example 2:

         my @uids;
         foreach $r ($imap->UID("SEARCH","SUBJECT","Just a silly test") {
             chomp $r;
             $r =~ s/\r$//;
             $r =~ s/^\*\s+SEARCH\s+// or next;
             push @uids, grep(/\d/,(split(/\s+/,$r)));
         }

       In the second example, we used the default method to issue the UID IMAP client command, being careful to
       use an all-uppercase method name so as not to inadvertently call the "Uid" accessor method.  Then we
       parsed out the message UIDs manually, since we don't have the benefit of the built-in "search" method
       doing it for us.

       Please be very careful when turning the "Uid" parameter on and off throughout a script.  If you loose
       track of whether you've got the "Uid" parameter turned on you might do something sad, like deleting the
       wrong message.  Remember, like all eponymous accessor methods, the Uid method without arguments will
       return the current value for the "Uid" parameter, so do yourself a favor and check.  The safest approach
       is probably to turn it on at the beginning (or just let it default to being on) and then leave it on.
       (Remember that leaving it turned off can lead to problems if changes to a folder's contents cause
       resequencing.)

       By default, the "Uid" parameter is turned on.

   User
       Example:

         $User = $imap->User();
         # or:
         $imap->User($userid);

       Specifies the userid to use when logging into the IMAP service.  Can be supplied with the "new" method
       call or separately by calling the User object method.

       Parameters can be set during "new" method invocation by passing named parameter/value pairs to the
       method, or later by calling the parameter's eponymous object method.

Status Methods

       There are several object methods that return the status of the object.  They can be used at any time to
       check the status of an IMAPClient object, but are particularly useful for determining the cause of
       failure when a connection and login are attempted as part of a single "new" method invocation.  The
       status methods are:

   Escaped_history
       Example:

         my @history = $imap->Escaped_history;

       The Escaped_history method is almost identical to the History method.  Unlike the History method,
       however, server output transmitted literally will be wrapped in double quotes, with all double quotes,
       backslashes escaped.  If called in a scalar context, Escaped_history returns an array reference rather
       than an array.

       Escaped_history is useful if you are retrieving output and processing it manually, and you are depending
       on the above special characters to delimit the data.  It is not useful when retrieving message contents;
       use message_string or body_string for that.

   Escaped_results
       Example:

         my @results = $imap->Escaped_results;

       The Escaped_results method is almost identical to the Results method.  Unlike the Results method,
       however, server output transmitted literally will be wrapped in double quotes, with all double quotes,
       backslashes escaped.  If called in a scalar context, Escaped_results returns an array reference rather
       than an array.

       Escaped_results is useful if you are retrieving output and processing it manually, and you are depending
       on the above special characters to delimit the data.  It is not useful when retrieving message contents;
       use message_string or body_string for that.

   History
       Example:

         my @history = $imap->History;

       The History method is almost identical to the "Results" method.  Unlike the "Results" method, however,
       the IMAP command that was issued to create the results being returned is not included in the returned
       results.  If called in a scalar context, History returns an array reference rather than an array.

   IsUnconnected
       returns a true value if the object is currently in an "Unconnected" state.

   IsConnected
       returns a true value if the object is currently in either a "Connected", "Authenticated", or "Selected"
       state.

   IsAuthenticated
       returns a true value if the object is currently in either an "Authenticated" or "Selected" state.

   IsSelected
       returns a true value if the object is currently in a "Selected" state.

   LastError
       Internally LastError is implemented just like a parameter (as described in "Parameters", above).  There
       is a LastError attribute and an eponymous accessor method which returns the LastError text string
       describing the last error condition encountered by the server.

       Note that some errors are more serious than others, so LastError's value is only meaningful if you
       encounter an error condition that you don't like.  For example, if you use the "exists" method to see if
       a folder exists and the folder does not exist, then an error message will be recorded in LastError even
       though this is not a particularly serious error.  On the other hand, if you didn't use "exists" and just
       tried to "select" a non-existing folder, then "select" would return "undef" after setting LastError to
       something like "NO SELECT failed: Can't open mailbox "mailbox": no such mailbox".  At this point it would
       be useful to print out the contents of LastError as you die.

   LastIMAPCommand
       New in version 2.0.4, LastIMAPCommand returns the exact IMAP command string to be sent to the server.
       Useful mainly in constructing error messages when "LastError" just isn't enough.

   Report
       The Report method returns an array containing a history of the IMAP session up to the point that Report
       was called.  It is primarily meant to assist in debugging but can also be used to retrieve raw output for
       manual parsing.  The value of the "Clear" parameter controls how many transactions are in the report.

   Results
       The Results method returns an array containing the results of one IMAP client command.  It accepts one
       argument, the transaction number of the command whose results are to be returned.  If transaction number
       is unspecified then Results returns the results of the last IMAP client command issued.  If called in a
       scalar context, Results returns an array reference rather than an array.

   State
       The State method returns a numerical value that indicates the current status of the IMAPClient object.
       If invoked with an argument, it will set the object's state to that value.  If invoked without an
       argument, it behaves just like "Status", below.

       Normally you will not have to invoke this function.  An exception is if you are bypassing the
       Mail::IMAPClient module's "connect" and/or "login" modules to set up your own connection (say, for
       example, over a secure socket), in which case you must manually do what the "connect" and "login" methods
       would otherwise do for you.

   Status
       The Status method returns a numerical value that indicates the current status of the IMAPClient object.
       (Not to be confused with the "status" method, all lower-case, which is the implementation of the STATUS
       IMAP client command.)

   Transaction
       The Transaction method returns the tag value (or transaction number) of the last IMAP client command.

Custom Authentication Mechanisms

       If you just want to use plain text authentication or any of the supported "Advanced Authentication
       Mechanisms" then there is no need to read this section.

       There are a number of methods and parameters that you can use to build your own authentication mechanism.
       All of the methods and parameters discussed in this section are described in more detail elsewhere in
       this document.  This section provides a starting point for building your own authentication mechanism.

       There are many authentication mechanisms out there, if your preferred mechanism is not currently
       supported but you manage to get it working please consider donating them to this module.  Patches and
       suggestions are always welcome.

       Support for add-on authentication mechanisms in Mail::IMAPClient is pretty straight forward.  You create
       a callback to be used to provide the response to the server's challenge.  The "Authcallback" parameter
       contains a reference to the callback, which can be an anonymous subroutine or a named subroutine.  Then,
       you identify your authentication mechanism, either via the "Authmechanism" parameter or as an argument to
       "authenticate".

       You may also need to provide a subroutine to encrypt (or whatever) data before it is sent to the server.
       The "Prewritemethod" parameter must contain a reference to this subroutine.  And, you will need to
       decrypt data from the server; a reference to the subroutine that does this must be stored in the
       "Readmethod" parameter.

       This framework is based on the assumptions that a) the mechanism you are using requires a challenge-
       response exchange, and b) the mechanism does not fundamentally alter the exchange between client and
       server but merely wraps the exchange in a layer of encryption.  It also assumes that the line-oriented
       nature of the IMAP conversation is preserved; authentication mechanisms that break up messages into
       blocks of a predetermined size may still be possible but will certainly be more difficult to implement.

       Alternatively, if you have access to imtest, a utility included in the Cyrus IMAP distribution, you can
       use that utility to broker your communications with the IMAP server.  This is quite easy to implement.
       An example, examples/imtestExample.pl, can be found in the "examples" subdirectory of the source
       distribution.

       The following list summarizes the methods and parameters that you may find useful in implementing
       advanced authentication:

       The authenticate method
           The "authenticate" method uses the "Authmechanism" parameter to determine how to authenticate with
           the server see the method documentation for details.

       Socket and RawSocket
           The "Socket" and "RawSocket" methods provide access to the socket connection.  The socket is
           typically automatically created by the "connect" method, but if you are implementing an advanced
           authentication technique you may choose to set up your own socket connection and then set this
           parameter manually, bypassing the connect method completely.  This is also useful if you want to use
           IO::Socket::(INET|IP) alternatives like IO::Socket::SSL and need full control.

           "RawSocket" simply gets/sets the socket without attempting any interaction on it.  In this case, you
           have to be sure to handle all the preliminary operations and manually set the Mail::IMAPClient object
           in sync with its actual status with respect to this socket (see below for additional parameters
           regarding this, especially the "State" parameter).

           Unlike "RawSocket", "Socket" attempts to carry on preliminary connection phases if the conditions
           apply.  If both parameters are present, this takes the precedence over "RawSocket".  If "Starttls" is
           set, then the "starttls" method will be called by "Socket".

           PLEASE NOTE As of version 2.99_04 of this module, semantics for "Socket" have changed to make it more
           "DWIM".  "RawSocket" was introduced as a replacement for the "Socket" parameter in older version.

       State, Server, User, Password, Proxy and Domain Parameters
           If you need to make your own connection to the server and perform your authentication manually, then
           you can set these parameters to keep your Mail::IMAPClient object in sync with its actual status.  Of
           these, only the "State" parameter is always necessary.  The others need to be set only if you think
           your program will need them later.

       Authmechanism
           Set this to the value that AUTHENTICATE should send to the server as the authentication mechanism.
           If you are brokering your own authentication then this parameter may be less useful.  It exists
           primarily so that you can set it when you call "new" to instantiate your object.  The "new" method
           will call "connect", which will call "login".  If "login" sees that you have set an Authmechanism
           then it will call authenticate, using your Authmechanism and Authcallback parameters as arguments.

       Authcallback
           The "Authcallback", if set, holds a pointer to a subroutine (CODEREF).  The "login" method will use
           this as the callback argument to the authenticate method if the Authmechanism and Authcallback
           parameters are both set.  If you set Authmechanism but not Authcallback then the default callback for
           your mechanism will be used.  All supported authentication mechanisms have a default callback; in
           every other case not supplying the callback results in an error.

           Most advanced authentication mechanisms require a challenge-response exchange.  After the
           "authenticate" method sends "<tag> AUTHENTICATE <Authmechanism>\015\012" to the IMAP server, the
           server replies with a challenge.  The "authenticate" method then invokes the code whose reference is
           stored in the Authcallback parameter as follows:

             $Authcallback->( $challenge, $imap )

           where $Authcallback is the code reference stored in the Authcallback parameter, $challenge is the
           challenge received from the IMAP server, and $imap is a pointer to the Mail::IMAPClient object.  The
           return value from the Authcallback routine should be the response to the challenge, and that return
           value will be sent by the "authenticate" method to the server.

       Prewritemethod/Readmethod
           The Prewritemethod can hold a subroutine that will do whatever encryption is necessary and then
           return the result to the caller so it in turn can be sent to the server.

           The Readmethod can hold a subroutine to be used to replace sysread usually performed by
           Mail::IMAPClient.

           See "Prewritemethod" and "Readmethod" for details.

REPORTING BUGS

       Please file bug reports via https://github.com/plobbes/mail-imapclient/issues

         Copyright (C) 1999-2003 The Kernen Group, Inc.
         Copyright (C) 2007-2009 Mark Overmeer
         Copyright (C) 2010-2021 Phil Pearl (Lobbes)
         All rights reserved.

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself, either Perl version 5.8.0 or, at your option, any later version of Perl 5 you may have available.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
       the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See either the GNU General
       Public License or the Artistic License for more details.